CAP Abstracts

CANADIAN ASSOCIATION OF PATHOLOGISTS ASSOCIATION CANADIENNE DES PATHOLOGISTES ABSTRACTS — RE´SUME´S 55TH ANNUAL MEETING 2004 MONTRE´AL, QUE´BEC 55ieme ASSEMBLE´E ANNUELLE JULY 3–7 2004 3–7 JUILLET 2004

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Abstracts / Pathology – Research and Practice 200 (2004) 631–655

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Utility of c-kit immunoreactivity in adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma M. AFROUZIAN1, K. BEREAN2 1 Department of Pathology, Foothills Medical Center, University of Calgary, Calgary, Alberta 2 Department of Pathology, UBC Hospital, University of British Columbia, Vancouver, BC

Objective: Adenoid cystic carcinoma (ACC) and polymorphous low-grade adenocarcinoma (PLGA) are low-grade malignant neoplasms of salivary gland with considerable morphologic overlap. Although the two tumors can be readily differentiated by routine histology in the majority of cases, occasionally this distinction is difficult. The distinction has considerable clinical importance, as PLGA is usually resectable and curable with conservative excision, while ACC requires radical excision and adjunctive radiotherapy and is seldom cured. In light of recent studies suggesting that c-kit immunohistochemical staining may be useful in separating these two tumors, we undertook the following immunohistochemical comparative study of PLGA and ACC. Methods: Formalin-fixed paraffin-embedded tissue from cases diagnosed as ACC and PLGA between 1983 and 2003 were retrieved from the files of the Vancouver Hospital and Health Sciences Center and the files of one of the authors (KB). Sections were stained with c-kit (rabbit polyclonal, DAKO) by routine methods. The c-kit-stained slides were evaluated for percentage of cell staining, intensity and pattern of staining. Results: The majority of ACC (16/20) showed diffuse (>50% of tumoral cells), moderate to strong positivity with c-kit. Both cytoplasmic and membrane staining were present in most cases (16/20). In all cases there was preferential staining of luminal cells. Two examples of ACC showed only focal positivity because of extensive basement membrane deposition with predominantly abluminal (myoepithelial) cells remaining. In contrast, in PLGA only 3/17 cases showed >50% positivity and only 2/17 cases showed membranous staining. Conclusions: ACC and PLGA show different reactivity with c-kit immunohistochemical staining, and may be a useful ancillary investigation in difficult cases.

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Leukemic phase in diffuse large-cell lymphoma: association with simultaneous t (14; 18) and t (8; 14) translocations. Report of 3 cases MAJID AKBARI, BRIGITTE ROLAND, ADNAN MANSOOR Department of Pathology, University of Calgary, Calgary, Alberta, T2N 2T9

Introduction: Over expression of various oncogenes, by virtue of chromosomal translocations, play a significant role in the pathogenesis of hematological malignancies. Anti-apoptotic bcl-2 protein; t (14; 18) in follicular lymphomas and cell cycle regulator c-myc gene, t(8;14) in Burkitt’s lymphoma are wellknown examples. Simultaneous presence of these two translocations (double hit) results in an accelerated proliferation. Only four cases of DLBCL with simultaneous presence of these two translocations have been reported. The leukemic presentation in DLBCL is also a rare event. We present three cases of diffuse large B-cell lymphoma exhibiting this dual translocation (double hit) and its association with leukemic phase. Methodology: Immunophenotyping was performed by routine flow-cytometry and immunoperoxidase techniques. Conventional cytogenetic/FISH analysis were performed to determine the presence of specific translocations. Result: Table 1, Clinical, IHC, cytogenetic. Conclusion: This dual translocation predicted an aggressive clinical course, as the lymphoma transformed into leukemic phase within a year of initial diagnosis. Routine cytogenetic analysis is recommended at initial diagnosis of NHL to better identify abnormalities that may predict prognosis.

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Epithelioid angiosarcoma of the bladder after therapeutic irradiation for endometrioid carcinoma MAJID AKBARI, ANDRZEJ KULAGA, ASLI YILMAZ, RICHARD P. WILKIN, KIRIL TRPKOV Department of Pathology, University of Calgary, Calgary, Alberta, T2V 1P9 Angiosarcomas of the bladder are extremely rare and only 11 cases have been reported to date. We report a patient who developed epithelioid angiosarcoma of the urinary bladder 14 years after radiation treatment for uterine endometrioid adenocarcinoma. To our knowledge, this is only the second epithelioid angiosarcoma documented in the urinary bladder. Case report: An 83-year-old female with microhematuria with a sessile nodular mass at the posterolateral bladder wall. Pathology showed a poorly differentiated epithelioid tumor with the epithelioid cells that infiltrated extensively into the bladder muscularis propria and exhibited sheet-like growth pattern with marked coagulative necrosis and apoptosis. Vasoformative areas were not apparent, but rare intracytoplasmic lumina were present. The neoplasm was composed of epithelioid cells. Tumor immunoprofile was in keeping with angiosarcoma and demonstrated diffuse tumor cell immunoreactivity for vimentin and vascular endothelial marker CD31. Negative immunostains included different cytokeratins (AE1/ AE3, CAM 5.2, CK5/6, CK 7 and CK20), EMA, S-100, and HMB-45. The patient died three months after the presentation.

Table 1 Case no.

Extranodal

Age/Sex

Stage

CD20

CD10

BCL2

Tdt

tð14; 18Þ

c-myc

1 2 3

Intestine Spleen Mesentery

63/F 38/F 68/M

IV IV IV

pos pos pos

pos pos pos

pos pos Pos

neg neg neg

Present Present Present

Rearrangement Present Present Present

Abstracts / Pathology – Research and Practice 200 (2004) 631–655

Conclusion: Epithelioid angiosarcoma with prior radiotherapy is unusual, as majority of radiation-associated angiosarcoma are conventional, rather than epithelioid, and they usually appear as surface, rather than visceral tumors. Of 11 patients with bladder angiosarcoma with documented follow-up (including the present case), eight died with a mean survival time of 7.9 months. Three patients had no evidence of recurrence or metastases at 8, 29, and 30 months of followup. Optimal therapy for bladder angiosarcoma remains to be determined and, given the aggressive nature of the disease, may include a multimodal approach, combining radical surgery, if the tumor is resectable, followed by radiotherapy and chemotherapy.

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lymph node metastases. These tumors exhibited insular and glandular patterns with amyloid stroma. The tumor cells expressed chromogranin, synaptophysin, cytokeratin, calcitonin and somatostatin and were negative for gastrin, Ki-67 and P53 by immunohistochemistry. This report highlights two cases of ampullary carcinoid tumors with amyloid stroma. Despite their aggressive behavior, these tumors lack the expression of cellular proliferation antigen Ki-67 and P53 suppressor gene.

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Intraventricular hemangiopericytoma: case report and literature review N. AL-BRAHIM1, R. DEVILLIERS2, J. PROVIAS1

Fine needle aspiration of solid pancreatic tumors

AL-ARDATI, J.M. RADHI Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ont., Canada Objective: The use of ultrasound-guided percutaneous fine needle aspiration biopsy is considered a safe and feasible method for diagnosis of solid pancreatic tumors. This study deals with the review of FNA biopsies and correlates the finding with core needle biopsy results. Method: The cytology records at McMaster Medical Center were searched for all FNAs and core biopsies of solid pancreatic tumor performed during 1992–2003. Emphasis was placed on the diagnostic categories, cell block availability and correlation with core needle biopsies present. Result: A total of 39 FNA cytology cases of solid pancreatic tumors were identified from the file. Nineteen cases were diagnosed as malignant, six cases reported as atypical cells, nine cases considered negative, and five cases determined as non-diagnostic/insufficient material for cytologic evaluation. Cell blocks were prepared in 28 cases of which the diagnosis of malignancy in three cases was made despite scanty smear findings. Meanwhile, core needle biopsies identified only one false-negative cytology. Conclusion: FNA cytology of solid pancreatic tumors is a reliable and sensitive method for diagnosis and is considered comparable in outcome to core needle biopsy results. Examination of cell blocks is very helpful and enhances diagnostic accuracy.

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1

Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ont., Canada 2 Department of Neurosurgery, McMaster University, Hamilton, Ont., Canada Background: Hemangiopericytoma is a rare tumor of the central nervous system and very rarely has been reported intraventricularly. Herein is a report of an intraventricular hemangiopericytoma. Case description: A 55-year-old female presented with gradual onset of left-side weakness, gait ataxia and tendency to miss objects in the left visual field of uncertain duration. MRI with contrast showed a tumor with homogenous enhancement in the right lateral ventricle. The patient underwent right temporoparietal stealth assisted craniotomy and surgical removal of the tumor. Histological examination showed a cellular neoplasm with slit-like vasculature some with stag horn appearance. There was minimal cytological atypia. Reticulin stain revealed dense reticulin fibers arrange around individual cells. Immunohistochemical stains demonstrated uniform expression of vimentin and CD34 and negative expression of AE1/AE3 and EMA. Conclusion: Awareness that Hemangiopericytoma can occur as an intraventricular tumor is important for clinicians and pathologists. Due to radiological similarity, this tumor is not to be confused with intraventricular meningioma since the prognosis is different.

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Malignant melanoma with osteoclast-like giant cells: a host response to a dedifferentiation? Immunohistochemical and ultrastructural study of three cases and literature review

Ampullary carcinoid with amyloid stroma N. AL-BRAHIM, S. SALAMA

N. AL-BRAHIM, J. RADHI Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ont., Canada Carcinoid tumors of ampulla of Vater are rare lesions with more aggressive behavior than their duodenal counterpart. Two patients presented with obstructive jaundice. ERCP demonstrated dilated common bile ducts and irregular ampulla. CT scans showed large peripancreatic lymph nodes. Biopsy of the ampulla in one case revealed an endocrine tumor and was negative in the other case. Pancreaticoduodenectomies were performed and revealed small ampullary carcinoid tumors and extensive peripancreatic

Department of Pathology and Molecular Medicine, McMaster University and St. Joseph’s Hospital, Hamilton, Ont., Canada Melanomas with unusual histological features are very rarely reported in the literature and demonstrate the diversity of melanocytic expression. Three cases of malignant melanoma with osteoclast-like giant cells are reported. Two cases showed undifferentiated malignant cells without melanin pigment and one showed spindle cell morphology. Immunohistochemistry revealed the osteoclast-like giant cells expressing the histiocytic marker CD68, but not the melanocytic markers (HMB45 and S100). Ultrastructural analysis confirms these cells to be reactive histiocytes rather than transformed malignant cells.

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This suggests they represent an unusual host response, similar to those rarely observed in other neoplasms. Awareness of this entity is important to avoid misdiagnosis of melanoma as a histiocytic tumor. Although the clinical follow up of these cases is short, the clinical presentation of the few previously reported cases with similar histology and one of the cases reported herein with local recurrences and lymph node metastasis suggests an aggressive behavior, possibly related to dedifferentiation.

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The value of postmortem examination in cases of metastasis of unknown origin (MUO)-20 year retrospective data from Hamilton region N. AL-BRAHIM, K. CHORNEYKO, C. ROSS, B. CARTER Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario Background: Metastasis of unknown origin (MUO) is a diagnostic challenge in clinical practice in even the presence of advanced diagnostic technology. In order to evaluate the value of autopsy in determining the primary site of MUO, this study reviewed the Hamilton experience over the last twenty years of patients autopsied with a clinical diagnosis of MUO. Methods: All autopsy diagnosis from cases performed at Hamilton Health Sciences Center and St. Joseph’s Health Care were reviewed from 1980–2000. Fifty-three cases of MUO were identified (MUO was defined as patient with pathological and/ or radiological diagnosis of metastatic tumor for which the primary site of malignancy was unknown). The clinical history, gross and microscopic diagnosis for these cases were reviewed. Results: There were 31 men (58.5%) and 22 women. The mean age was 66 years. Pathological diagnoses at autopsy were adenocarcinoma (37), small cell carcinoma (6), anaplastic carcinoma and undifferentiated carcinoma (3 cases each). Primary tumors were identified in 27 patients (51%) most commonly in the lung (8), large bowel (6) and pancreas (4). Histochemical and immunohistochemical stains were helpful in reaching the diagnosis of primary tumor in four cases out of 27. Interpretations: (1) In this series, autopsy was helpful in establishing the diagnosis of a primary tumor in 51% of cases, reaffirming the value of postmortem examination in these instances. (2) Adenocarcinoma was the most frequent tumor presenting as MUO. (3) The lung and the pancreas were the most frequent sites for primary tumors. (4) Careful gross and histological examination remain the most important tools in identifying the primary site.

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Giant cell interstitial nephritis associated with light chain deposition disease MAAMOUN AL-AYNATI1, KATHERINE CHORNEYKO1, DARIN TRELEAVEN2, IAKOVINA ALEXOPOULOU1 1 Department of Pathology and Molecular Medicine, St. Joseph’s Hospital and McMaster University, Hamilton, Ont., Canada

2

Department of Medicine, St. Joseph’s Hospital McMaster University, Hamilton, Ont., Canada.

and

The spectrum of renal lesions associated with light chain deposition disease is varied. We report the case of a 30-yearold man who presented with recurrent flank pain and acute renal insufficiency. The renal biopsy showed Kappa light chain deposition disease, without clinicopathological evidence of free monoclonal light chains in serum or urine, plasma cell dyscrasia, or amyloidosis. The patient progressed to chronic renal insufficiency and received a cadaveric renal transplant. However, his flank pain recurred and was cured by a right native nephrectomy. Pathological examination revealed an end-stage kidney with nodular expansion of the mesangium in the few functional remaining glomeruli. The striking finding was of florid foreign body-type giant cell reaction surrounding the atrophic tubules, obsolescent glomeruli and blood vessels in the absence of myeloma cast nephropathy. This is an unusual histological reaction to light chain deposition disease, that we report for the first time in the English literature.

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Diffuse large B-cell lymphoma of bone: correlation of clinical behavior with immunophenotypic and molecular genetic studies

E. ALKUWARI1, M. LAMBA1,2, D.H. GRAVEL1, D. SENGAR2, I. BENCE-BRUCKLER3, B.F. BURNS1 1 Anatomical Pathology Department, Ottawa Hospital and University of Ottawa, Ont., Canada 2 Hematopathology Department, Ottawa Hospital and University of Ottawa, Ont., Canada 3 Hematology Division of Medicine, Ottawa Hospital and University of Ottawa, Ont., Canada

Objective: An analysis was performed on three cases of diffuse large B-cell lymphoma (DLBCL) of bone to assess the immunohistochemical and molecular features of germinal center (GC)- and Non-GC stages of B-cell differentiation with clinical correlation to patients’ outcome and prognosis. Methods: Information was obtained regarding each patient’s presentation and clinical course. Histology was reviewed in all cases. Immunohistochemical and molecular studies were performed. BCL2 and BCL6 gene rearrangements were investigated by polymerase chain reaction. Data and results: One patient had a primary unifocal disease (stage I), the other had a unifocal bone disease with lymphadenopathy (stage IV) and the third patient had multifocal bone disease with lymphadenopathy (stage IV). The first case (stage I) showed a positive immunohistochemical reaction to BCL6 and CD10 with less than 5% expression of MIB-1. This represents GC-stage of B-cell differentiation. Molecular studies for BCL6- and BCL2-IgH rearrangement were unsuccessful, because of poor quality of RNA and DNA from decalcified paraffin block. This patient has no evidence of disease on follow-up (12 months). The other two cases (patients with stage IV) showed immunohistochemical negativity to BCL6 and CD10 with more than 85% expression of MIB-1. BCL2-IgH rearrangements were negative. BCL6-IgH rearrangements were unsuccessful. These two patients passed away at 7 and 25 months post diagnosis.

Abstracts / Pathology – Research and Practice 200 (2004) 631–655

Conclusions: DLBCL of bone with GC-like immunophenotype (BCL6+/CD10+) and low expression of MIB-1 may represent a subtype with improved outcome. The cases with NonGC immunophenotypic signature (BCL6/CD10), high expression of MIB-1 and absence of BCL2-IgH rearrangement are associated with poor survival.

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Effectiveness of scrape cytology in the cytology in the intraoperative assessment of sentinel lymph node biopsies

B. BALACHANDRA1, J. DANYLUK2 1 Department of Lab Medicine and Pathology, University of Alberta, Edmonton, Alberta 2 Department of Laboratory Medicine, Misericordia Community Hospital, Edmonton, Alberta

Axillary lymph node status is the most important predictor of disease-free survival in breast cancer. Sentinel lymph node (SLN) biopsy identifies the lymph node most likely to contain a metastasis. An intraoperative assessment (IOA) of SLN can determine whether or not a lymph node is positive, which allows for immediate lymphadenectomy. Objective: To determine the effectiveness of scrape cytology (SC) in the IOA of SLN and compare it to other techniques such as frozen section and imprint cytology. Methods: Patients that had an IOA of their SLN between January 2001 and December 2002 were selected. Cases were analyzed for age and sex distribution. SC results were compared to the paraffin section result and analyzed for specificity, sensitivity, false negative rate, false positive rate and accuracy. These results were compared to the published results for frozen section and imprint cytology. Results: IOA using SC was performed on 155 female patients, with a mean age of 57. Ductal carcinoma was the most common histological type (119/155, 77%). SC technique had a false positive rate of 5%, and a false negative rate of 17%. Sensitivity was 83%, specificity was 95% and the overall accuracy was 94%. There were four false negative cases and six false positive cases. In the true negative category, there were 21 cases with a metastasis size of p2 mm (micrometastasis). Our results are comparable to the published results of frozen section and imprint cytology. Conclusion: Scrape cytology is an effective technique in the intraoperative assessment of sentinel lymph node biopsies.

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In vivo detection of enzyme activity in a rat C6 glioma

model B.J. BEDELL1,2, S. MZENGEZA2, R.F. DEL MAESTRO3, S. ASSADIAN2,3, A.C EVANS2 1

Department of Pathology, McGill University McConnell Brain Imaging Center, 3 Brain Tumor Research Center, Montreal Neurological Institute, McGill University, Montreal, QC, Canada 2

Introduction: The activity and/or level of expression of hydrolytic/proteolytic enzymes, such as matrix metalloproteinases (MMPs) and cathepsins, are often increased in malignant tumors relative to benign conditions and normal tissue. The increased activity of these enzymes is thought to play a pivotal

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role in tumor invasion, metastasis, and angiogenesis. Further, the increased intra-tumoral activity of a number of hydrolytic enzymes has been exploited for the development of novel cancer chemotherapeutics using ‘‘prodrug’’ strategies. The ability to detect the activity of these enzymes in vivo would carry profound ramifications in the fields of molecular diagnostics and targeted therapeutics. We have, therefore, developed novel MRI ‘‘probes’’ which allow for specific, non-invasive, in vivo detection of hydrolytic enzymes. These probes have been evaluated, in vivo, in a rat implanted with C6 glioma spheroids. Methods: We have utilized an enzymatic activation/amplification strategy to overcome the inherently low detectability of conventional MRI probes. We have synthesized ‘‘bipartite probes’’, consisting of a probe conjugated to a ‘‘specifier’’. After systemic administration, the probe remains ‘‘invisible’’ to the MRI scanner until the specifier moiety is cleaved by the targeted enzyme. The enzyme then amplifies the number of ‘‘activated’’ probes, rendering them visible on MR images. Results: The probes have been fully characterized by chemical analyses and in vitro MRI studies. Following systemic administration, the probes successfully demonstrated the presence of hydrolytic enzymes localized to C6 gliomas implanted into male Sprague–Dawley rats. Appropriate control studies have been performed. Conclusions: Our probes represent a new class of molecular diagnostic agents which should find numerous applications, including the evaluation of novel, targeted therapeutic agents.

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Epithelioid angiomyolipoma of the kidney mimicking renal sarcoma. A comparative study with carcinoma-like epithelioid angiomyolipoma

ERIC C. BELANGER, PRASHANT DHAMASKAR, A. SUSAN COMMONS, HOSSEIN M. YAZDI, KIEN T. MAI Department of Pathology and Laboratory Medicine, The Ottawa Hospital, Civic Campus and University of Ottawa, Ottawa, Ont,. Canada Background: Renal epithelioid angiomyolipoma (EAML) often mimics renal cell carcinoma. We report a type of sarcoma-like EAML mimicking renal sarcoma. Design and results: A pilot case consisted of a sarcomatoid renal neoplasm with multinucleated giant cells and rare atypical epithelioid cells. The tumor showed strong immunoreactivity for HMB-45 and MART-1 and focal immunoreactivity for vimentin, CD68, smooth muscle actin, cytokeratin and epithelial membrane antigen. Immunoreactivity for S-100, chromogranin A, synaptophysin, muscle-specific actin, CD10, renal cell carcinoma antigen and CD117 was negative. Eleven consecutive renal carcinosarcomas and eight renal sarcomas were obtained from the files at our institution. One tumor from the carcinosarcoma group and one tumor from the sarcoma group displayed similar immunohistochemical features as seen in the pilot case, with the exception of positive immunoreactivity for S-100 in large areas in the case from the carcinosarcoma group. Patients in these three cases ranged in age from 42 to 54 years. The M:F ratio was 2:1, and the tumors were between 10 and 12 cm in diameter. Two patients died, 1 and 2 years later, the remaining one was alive with lung metastases. Comparisons were made with four carcinoma-like EAML from our institution. The multinucleated giant cells

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were less frequent, whereas the necrosis was as extensive. Mitotic figures were more frequent in sarcomatoid EAML. Three of four patients died of the disease due to local recurrence or distant metastases, the remaining one was free of disease after 5 years of follow-up. Conclusions: Renal sarcoma should be screened with HMB-45, since EAML is histogenetically a different entity. Sarcoma-like EAML appears to be more aggressive than non-sarcomatoid tumors.

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PEComa of the soft tissue

ERIC BELANGER, A. SUSAN COMMONS, HOSSEIN M. YAZDI, KAREN L. BURNS, KIEN T. MAI Department of Pathology and Laboratory Medicine, The Ottawa Hospital, and University of Ottawa, Ottawa, Ont,. Canada Background: PEComa is a rare tumor developing from perivascular epithelioid cells (PEC) that are characterized by positive immunoreactivity for HMB45 and are believed to be present in many organs and in soft tissue. Design: Consecutive 31 soft tissue sarcomas spanning a 3-year period and 10 consecutive dermatofibromas were retrieved from the surgical pathology file at our institution and immunostained for HMB45. Cases with positive HMB45 immunostaining were submitted for further immunostaining for MART1, CD68, S100 protein, cytokeratin AE 1 and AE3, epithelial membrane antigen (EMA), vimentin, muscle-specific actin (MSA), smooth muscle actin (SMA) and CD117. Results: Of all review cases, four tumors in the group of 11 MFH and unclassified sarcomas showed positive immunoreactivity for HMB45 and MART1 in small groups of cells accounting for 1–10% of tumor cells. The tumors were located in the lower extremities and measured from 2 to 11 cm in diameter. The patients ranged in age from 33 to 60 years. Microscopically, the tumors were composed of a variable proportion of spindle cells, multinucleated cells and epithelioid cells disposed in diffuse sheets and nests. Mitotic figures and necrosis were frequent. The immunoreactivity was diffuse for CD68 focal for each of AE1, AE3 and EMAnegative or focal for SMA, MSA and CD117 and negative for S100. Three of four patients developed lymph node or distant metastasis and died of the disease within 2–3 years of diagnosis. In addition, one of two alveolar soft part sarcomas showed weak but diffuse immunoreactivity for HMB45 and MART1 and focal immunoreactivity for S100 protein. Conclusions: Screening of undifferentiated and epithelioid sarcomas with immunostaining for HMB45 is useful to further characterize some unclassified tumors. The significance of alveolar soft part sarcoma with weakly HMB45-immunoreactive cells remains unknown.

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An unusual anal polyp far from home

N.G. CHAN1, J.L. PENSWICK2, D.K. DRIMAN1 1

Departments of Pathology, London Health Sciences Center and the University of Western Ont, London, Ont., Canada N6A 5A5 2 Timmins and District Hospital, Timmins, Ont., Canada P4N 8P2

We report a case of an unusual polyp in the anal canal of a 46-year-old woman. The patient’s medical history is significant for adenomatous polyps, irritable bowel syndrome, diverticular disease, endometriosis, ovarian mucinous cystadenoma, and a family history of colorectal neoplasia. She presented with an 8-month history of an intermittently prolapsing lesion which caused discomfort and worsened during bowel movements. Examination revealed a large, soft, mobile cystic lesion on the right posterior aspect of the anal canal. It was initially thought to be a large hemorrhoid but its cystic nature was unusual. The lesion was surgically excised. On gross examination, it was an irregularly shaped tan polyp measuring 2.5 cm in greatest dimension. Sectioning revealed firm pink-tan tissue with a cystic component containing clear fluid. Microscopic examination showed a polypoid fragment of tissue lined on the outer aspect by squamous epithelium with hyperkeratosis and focal parakeratosis. Within the core of the polyp, there were mammary ducts and lobules with focal apocrine metaplasia. Some of the duct epithelium showed mild epithelial hyperplasia. Many of the ducts were cleft-like and dilated, imparting a fibroadenomatoid appearance. The stroma was not hypercellular and there was no evidence of malignancy. Features of hidradenoma papilliferum were absent. Immunohistochemistry showed diffuse positivity for cytokeratin 7 and progesterone receptor protein and focal positivity for estrogen receptor protein. The pathological features were those of breast tissue. To the best of our knowledge, this is the first documented case of ectopic breast tissue arising in the anus, and presenting as an anal polyp.

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Characterization of post-transplant lymphoroliferative disorders in orthotopic liver transplant recipients

N.G. CHAN1, J.G. SHEPHERD1, P.J. MAROTTA2, C.N. GHENT2, K.S. RIZKALLA1 1 Department of Pathology, London Health Sciences Center and the University of Western Ont, London, Ont., N6A 5A5, Canada 2 Department of Gastroenterology, London Health Sciences Center and the University of Western Ont, London, Ontario, N6A 5A5, Canada

Post-transplant lymphoproliferative disorders (PTLD) are a serious and often fatal disease in solid organ transplant recipients developing as a consequence of immunosuppression. The London Health Sciences Center is a major transplant center, with 1088 patients receiving orthotopic liver transplants (OLT) between 1986 and January 31, 2004. Of these, we have 25 documented cases of PTLD, for an overall incidence of 2.3%. The objectives of our study include (1) examining the histology and identifying the key diagnostic features of PTLD in OLT patients, (2) identifying the differences in histology between immunosuppression-related and non-immunosuppression-related lymphoproliferative diseases, and (3) determining the feasibility of applying the WHO classification. Preliminary results show that the morphology of PTLD in OLT patients range from benign plasmacytoid hyperplasia to aggressive diffuse large B-cell and Burkitt’s lymphomas. More than half of the cases have aggressive disease; diffuse large B-cell lymphoma is the predominant pattern. EBVLMP1 and/or EBER is positive in 18/24 cases for an overall incidence of 75%. Results also show histologic differences

Abstracts / Pathology – Research and Practice 200 (2004) 631–655

between the two groups. In PTLD, there is variable histology both within the same tumor and between different sites of an individual, ranging from plasmacytoid hyperplasia to large cell lymphoma. The behaviour of PTLD differ in their tendency to regress with decreased immunosuppression. Also unique to PTLD are the presence of many background T lymphocytes and differences in EBV-staining pattern. The WHO classification is a useful guideline in classifying PTLD in our patients. We conclude that PTLD developing in OLT patients have unique histology. Adequate sampling and precise evaluation are required for proper assessment to determine clinical prognosis and treatment.

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Plasma transfusion trigger determination using relational database methods

K.W. CHENG CALVINO1, SUSAN N. NAHIRNIAL1 1 Department of Laboratory Medicine and Pathology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, T6G 2B7

Objective: Relational databases (RDs) are used widely in business but are virtually nonexistent in the medical literature. In this study, we used RDs to evaluate plasma transfusion triggers in the adult ðageX17 yearsÞ and pediatric populations. Methods: Retrospectively, transfusion (txn) data tables from the lab information system (Misys) from April 1, 2002 and March 31, 2003 were merged using a unique patient identifier field with coagulation data tables in Microsoft Access 2000. A combined INR/Txn table was obtained using all transfusion instances (TIs) first. The records within the INR table were then combined using a one-to-one relationship with a PTT table via the unique patient identifier. This resulted in the PTT/ INR/Txn table. Patients transfused plasma for thrombotic thrombocytopenic purpura were excluded. Data analysis used SPSS 11.01. Results: A total of 1185 TIs were examined. Of these, 1107 (93.4%) had timely coagulation testing (o 24 h old), with 159 (14.3%) pediatric TIs and 948 (85.6%) adult TIs. In the pediatric group, 155 TIs had mean triggers of INR ¼ 2:3 and PTT ¼ 80:4s. An average of 1.4 units of plasma were transfused at an average of 4.2 h after testing. In the adult group, 826 TIs had mean triggers of INR ¼ 2:7 and PTT ¼ 51:6s. An average of 2.7 units of plasma were transfused at an average of 4.4 h after testing. Conclusions: Plasma transfusion triggers generated by the RDs were deemed appropriate in both age groups. The use of relational database methods to ascertain transfusion triggers is a novel concept in transfusion literature. This may be applied to other blood products to provide feedback on ward or physician compliance; to adequately utilize and conserve blood products; and to benchmark against national or international recommendations.

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ZAP-70 expression in mantle cell lymphoma correlates with worse clinical outcome

K.W. CHENG CALVINO1, ATHER BANO1, ANDREW BELCH2, TONY REIMAN2, A. ROBERT TURNER2, LAITH DABBAGH2, JOHN HANSON2, GEORGIOS Z. RASSIDAKIS3, HESHAM AMIN3, RAYMOND LAI1,2

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1

Department of Laboratory Medicine and Pathology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, T6G 2B7 2 Cross Cancer Institute, Edmonton, Alberta 3 Department of Hematopathology, the University of Texas M.D. Anderson Cancer Center, Houston, Texas Objective: ZAP-70 has been shown to be a prognostic factor for patients with chronic lymphocytic leukemia. We examined the expression and prognostic value of ZAP-70 in mantle cell lymphoma (MCL). Methods: Forty-five consecutive MCL cases with cyclin D1 immunoreactivity were included. Expression of ZAP-70 was assessed using standard immunohistochemical staining techniques in formalin-fixed tissue sections and scored as negative, 1+ (weak), 2+ (moderate) and 3+ (strong). Results: Of the 45 tumors, 26 (57%) were positive, defined as 4 50% of MCL cells showing 1+ or 2+ staining intensity. Patients with ZAP-70-positive tumors were slightly younger ðP ¼ 0:047Þ. Overall, 26 (57%) patients died (median interval: 18 months). ZAP-70 positivity correlated with shorter overall survival (median time to death: 14 versus 35 months, P ¼ 0:038, age adjusted, logrank). The 3-year overall survival for patients with ZAP-70 positive tumors was 27% compared with 76% for patients with ZAP-70 negative tumors (P ¼ 0:015, logrank). The outcome of the 7 patients with tumors containing more than 70% of 2+ MCL cells was dismal (median survival: 7 months). Multivariate analysis confirmed the independent prognostic significance of ZAP-70 expression in this series. In one MCL tumor containing nodules of large neoplastic cells, ZAP-70 expression was higher in the transformed nodules compared with the small cell areas. Conclusions: ZAP-70 expression is relatively frequent in MCL, and high ZAP-70 expression appears to be associated with worse clinical outcome and possibly histologic progression.

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Downregulation of PTEN expression predicts relapse in patients with breast carcinoma treated by tamoxifen N. SHOMAN, A. MCFADDEN, M. BICKIS, S. KLASSEN, S. CARLSEN, E. TORLAKOVIC, R. CHIBBAR University of Saskatchewan, Saskatoon

Tamoxifen treatment substantially improves the 10-year survival of women with estrogen-receptor (ER) positive tumors. However, only two-thirds of all breast cancer patients with ER-positive tumors initially benefit from anti-estrogen therapy and 30–40% of ER positive tumors progress on antiestrogen therapy. Antiestrogen-resistant phenotype of breast carcinoma is not completely understood. Tamoxifen induces apoptosis by affecting estrogen regulated genes. The Phosphatase and Tensin homolog deleted on chromosome Ten (PTEN) gene is a novel candidate tumor suppressor that plays an important role in apoptosis and in the control of tumorinduced angiogenesis. A few studies have investigated the role of PTEN in the tumorigenesis of sporadic breast cancer. Decreased PTEN protein expression in breast cancer correlates with disease-related death, lymph node metastasis and loss of ER staining. In the endometrium and the breast, estrogen and progesterone regulate PTEN expression. The prognostic significance of PTEN protein loss as a marker of response to

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tamoxifen treatment is unknown. It may be possible that in a subset of ER alpha positive breast cancer, deregulation of PTEN expression is associated with unresponsiveness/resistance to tamoxifen treatment. The aim of this work was to determine the extent of PTEN expression in invasive breast cancer, and whether PTEN expression correlates with response to adjuvant hormonal therapy with tamoxifen. Protein expression of PTEN was also correlated with ER alpha, progesterone receptor, estrogen receptor beta, bcl-2, p53, and c-erbB-2. PTEN, ER alpha, progesterone receptor, ER beta, bcl-2, p53, and c-erbB-2 expression were studied by immunohistochemistry in 100 patients with ER positive invasive breast carcinoma treated with tamoxifen following surgery. Fiftyseven patients had recurrence and 43 patients had at least a 5year uneventful survival. Our results showed significant correlations between reduced PTEN expression (none to weak) and adverse prognostic factors in breast cancer, including steroid receptor loss, lymph node metastasis and diseaserelated death. More importantly, we have found a statistically significant association between downregulation of PTEN expression and progression on tamoxifen treatment characterized by disease recurrence or overall survival.

20

Appendiceal carcinoids in a pediatric population: an immunohistochemical analysis

M. CURTIS, G. TAYLOR, B. NGAN Hospital for Sick Children, Toronto, Ontario Carcinoid is the most common tumor of the appendix in children. The tumors are reported to be mostly incidental findings in approximately 1% of patients with a clinical diagnosis of appendicitis. There is a female predominance and an average age of 12–13. There has been very little research done on the immunohistochemical staining patterns of these tumors. We reviewed the files at the Hospital for Sick Children to find carcinoids of the appendix. There have been eight cases since 1989, or 0.5% of appendectomies. The patients included 5 females and 3 males, with an average age of 14 (range 11–16). The tumors varied between 7 and 15 mm in size. Five tumors involved the appendiceal tip, two involved the midportion, and one was diffuse. The patient with the diffuse tumor had a positive surgical resection margin and infiltration of mesenteric tissue. She had a right hemicolectomy which found residual tumor and a lymph node metastasis. We stained all eight primary tumors and the lymph node metastasis with a panel that included those stains used to diagnose small round blue cell tumors of childhood. Our findings confirm the reported clinical findings in regards to age, sex, location, and size. We also found that 100% of the tumors stained with chromogranin, NSE, serotonin, LMWK, S-100, CD56, and NB84; 75% with CD99; 67% with synaptophysin; and 0% with vimentin, CD45, and WT1. The lymph node metastasis stained with CD44. These findings give some information about the origin of carcinoids and help to differentiate carcinoid from other small round blue cell tumors seen in children. The finding of CD44 in metastatic carcinoid also gives some information about its mechanism of metastasis.

21

Quantitative microscopic evaluation of osteoarthritis and osteoporosis by magnetic resonance imaging (MRI)

V. DANIELS1,2, M. WEBER1,2, P. LATTA2, L. BLUHM1, F.W. ORR1 1

Department of Pathology, Winnipeg, MB 2 National Research Council Biodiagnostics, Winnipeg, MB

University of

of

Manitoba,

Canada—Institute

for

Background: High-resolution MRI generates non-invasive images of tissue structure with levels of resolution comparable to low-magnification histology. We have examined the ability of MR imaging to quantify the cartilaginous and osseous changes associated with osteoarthritis and osteoporosis as compared to micro X-ray and histology. Design: Femoral heads excised from patients undergoing hip replacement surgery were examined using an 11.7 T MR scanner followed by micro X-ray and histomorphometry. A thresholding algorithm was applied to all images (including histology) to quantify the density of bone in the subarticular regions of the femoral heads and the thickness of the articular cartilage. Results: We created correlation curves comparing each imaging modality to the histological gold standard with the slope (m) of the curve representing the accuracy of the modality and the correlation coefficient ðR2 Þ representing the precision or reproducibility. Optimal correlations of bone density with histology were found with gradient echo sequences (m ¼ 0:999, R2 ¼ 0:679  pp0:001), with an inplane resolution of 117 mm  117 mm and slice thickness of 350 mm. Micro X-ray was less precise (R2 ¼ 0:43, p ¼ 0:02). The results suggest that MR imaging may be superior to micro X-ray in the quantification of trabecular bone. This was confirmed by statistical analysis (repeated measures ANOVA with Duncan’s multiple comparison pp0:0001). The MR imaging modalities were also found to be accurate ð0:71o mo 0:85Þ and precise ðR2 4 0:86  pp0:0001Þ in the quantification of cartilage. Conclusion: Our results suggest that magnetic resonance imaging may be able to accurately assess cartilaginous and osseous structures to the level of histology at low magnification.

22

The effects of non-ionic contrast media in the cytopathology of urothelial malignancies

NEIL DWYER1, MICHEL DIONNE2, MATT BOWES2, JOHN GRANTMYRE1, LAURETTE GELDENHUYS2, REBECCA MACINTOSH2 1 Division of Urology, Dalhousie University and Queen Elizabeth II Health Sciences Center, Halifax, Nova Scotia 2 Division of Anatomical Pathology, Dalhousie University and Queen Elizabeth II Health Sciences Center, Halifax, Nova Scotia

Background: Urothelial malignancies of the upper urinary tract can be diagnosed with combined retrograde pyelography and urine brush cytology. It is desirable to perform the retrograde pyelography prior to the cytological sampling. It has been

Abstracts / Pathology – Research and Practice 200 (2004) 631–655

reported that ionic contrast media used for imaging cause degenerative changes in the cells, which complicate cytological analysis. Objective: To study the effects of non-ionic contrast media on urothelial cytomorphology. Methods: We quantified the effects of non-ionic contrast on urothelial cytomorphology and compared the results to those of control samples and samples exposed to ionic contrast. Urine specimens were obtained from patients presenting to the QEII for cystoscopy, and divided into five samples (control, 25% and 50% dilution with non-ionic contrast, and 25% and 50% dilution with ionic contrast). The resulting cytology slides were analyzed independently by two blinded cytopathologists. Cellularity and diagnosis were recorded. Features examined included smudged nuclear chromatin, karyorhexis and lysis, and cytoplasmic degeneration. Results: Twenty-three specimens were obtained, 20 of which were adequate for analysis. Nuclear smudge was higher in the samples diluted with either contrast as compared to the controls. No statistically significant differences were observed between samples diluted with ionic contrast versus non-ionic contrast. Conclusion: Use of more expensive non-ionic contrast did not decrease the cytological artifact.

23

Endocervical-type mucinous ovarian tumors: a clinicopathological analysis of 17 cases

VALE´RIE DUBE´1, BERNARD TEˆTU2 1

Department of Pathology, CHUQ, L’Hoˆtel-Dieu de Que´bec and Division of Pathology 2 Department of Medical Biology, Universite´ Laval Objective: Endocervical-type mucinous ovarian tumors (EMOT) are a less prevalent variant of tumors displaying a papillary architecture with a mucinous epithelial lining similar to the cervix. According to previous reports, EMOT affect young women, are diagnosed at an early stage, and follow a favorable course. Because of a presumably high bilaterality rate (40%), the optimal treatment has not been clearly established yet. The present study was conducted to reassess the clinical behavior of this tumor and thus consider a more conservative treatment than the current recommended bilateral salpingo-oophorectomy for those patients willing to preserve their fertility. Method: We reviewed every available slides and patients charts of all cases of EMOT found at l’Hoˆtel-Dieu de Que´bec. Macroscopic, histologic and clinical data was recorded. Results and conclusion: We found 17 cases of EMOT, among which 12 were borderline tumors, two were intra-epithelial carcinomas, two were micro-invasive carcinomas and one was an invasive carcinoma. Patients were diagnosed at an early stage, except for two patients (stage IIA and IIIC). Only two patients (12%) had bilateral tumors and seven underwent a conservative surgical treatment. Follow-up was available in 15 patients; one died of an unrelated cause. Every other patient is alive without disease, even those that displayed severe atypias, high mitotic rate, carcinoma, micro-invasion, invasion or advanced stage. A conservative surgical treatment seems therefore appropriate because the prognosis is favorable, the bilaterality rate is lower than first reported, and such conservative treatment does not predispose to recurrence or affect prognosis.

24

639

Papillary lesions in needle core biopsies

L.J. ELAVATHIL1, F. MOTHAFER1, T. MINUK2, D. FRANIC2 1 Department of Pathology, Hamilton Health Sciences, Hamilton, Ontario 2 Department of Radiology, Hamilton Health Sciences, Hamilton, Ontario

Objective: Needle core biopsy diagnosis plays an important role in planning the management of breast diseases. Our current standard of practice is to recommend subsequent excisional biopsy in all cases of papillary lesions diagnosed by needle core biopsy. Recent studies recommend that benign papillary lesions need not be excised but can be safely followed. Hence, the objective of our study is to determine the accuracy of core biopsy diagnoses of papillary breast lesions. Material and method: Fifty-one cases of papillary lesions were identified retrospectively at the Henderson Hospital from 1997–2001. Forty-seven cases which had subsequent excisional biopsies were included in the study. Three H&E slides and one actin stain from each core biopsy were reviewed (without the knowledge of the excisional biopsy) and classified as papilloma, papilloma with atypical ductal hyperplasia (ADH), papillary carcinoma and invasive papillary carcinoma. The excisional biopsies were similarly classified. Results: The age of the patients ranged from 34–77 years (mean 63 years). The needle core biopsies were classified as benign papilloma 25 cases (53%), papilloma with ADH 9 cases (19%), papillary carcinoma 13 cases (27%), intraductal carcinoma 11/13 (85%), invasive carcinoma 2/13 (15%). The incidence of carcinoma in subsequent excisional biopsies was as follows: 0/25 cases of papilloma, 7/9 cases of papilloma with ADH, and 12/13 cases of papillary carcinoma. Conclusion: In our population, needle core biopsy diagnoses of benign papillary lesions proved to be accurate when compared to excisional biopsy findings. Surgical excision was indicated in cases when needle core biopsies were diagnosed as papillary lesions with ADH or papillary carcinomas. A prospective study with follow-up is required to assess the clinical outcome of benign papillary lesions that are not excised after needle core biopsy.

25

Benign Hurthle cell neoplasm with papillary architecture: a lesion mimicking Hurthle cell papillary thyroid carcinoma GHAZI ELMONTASER, KIEN T. MAI, SUSAN COMMONS, HOSSEIN M. YAZDI, JANE THOMAS Department of Laboratory Medicine, The Ottawa Hospital and Department of Pathology and Laboratory Medicine, University of Ottawa, Ont., Canada Introduction: We studied the significance of encapsulated Hurthle cell thyroid nodules with papillary structures and without diagnostic nuclear features of papillary thyroid carcinoma (PTC). Materials and methods: Nineteen cases of encapsulated neoplastic Hurthle cell thyroid nodules with papillary

640

Abstracts / Pathology – Research and Practice 200 (2004) 631–655

structures accounting for more than 10% of tumor architecture without nuclear features diagnostic of PTC were obtained. Results: The patient ages ranged from 22–40 years ð32  6Þ with F:M ratio of 5:1 The tumors measured from 0.5–5 cm ð2  1:1Þ. The diameter of the nuclei ranged from 5.6 to 7:2 mm and were smaller than those of PTC (6.3–10:0 mm). Many nodules had nuclei displaying a fine chromatin pattern or nuclear features of papillary thyroid carcinoma (PTC), however, these features were observed in less than 20% of tumor cells and therefore not diagnostic of PTC. Immunostaining revealed positive reactivity for MIB1 in the papillary structures. Immunostaining varied from negative or focally weak reactivity for HBME and galactin-3 and negative to diffusely moderate reactivity for CK19. Clinical follow-up from 1 to 19 years revealed no evidence of metastasis. Conclusions: It is unlikely that the papillary structures in the study cases represent degenerative changes due to their proliferative activity. In view of (1) the encapsulation and the uniformity of the constituent cells, (2) the negative or weak immunoreactivity for galactin-3 and HBME and negative to moderate immunoreactivity for CK19, and (3) the absent or insufficient nuclear criteria for the diagnosis of PTC and (4) the absence of lymph node metastasis in all study cases, we believe that these lesions represent the papillary variant of follicular adenoma. Recognition of this pathological entity is important to avoid an over-diagnosis of Hurthle cell PTC.

26

Bacterial infection as a cause of hemoptysis in pulmonary aspergilloma

M.A. FAGIH, R.S. FRASER McGill University Health Center, Montreal, Quebec, Canada Objective of the study: Hemoptysis is a common presenting symptom of pulmonary aspergilloma. Several possible causes of such hemoptysis have been proposed, including local infiltration of the cavity wall by the fungus and tissue damage by calcium oxalate or biochemical toxins produced by fungi within the ball itself. We hypothesized that bacterial infection, either as a superinfection of the fungal cavity de novo or following saprophytic colonization of the fungus ball, might be responsible for tissue damage and hemoptysis in some cases. Methods: Twelve cases of pulmonary aspergilloma were retrieved from the surgical pathology files of the MUHC from 1993–2003. Appropriate slides were stained with H/E, Grocott and Gram stains and examined by polarization microscopy. The cavity wall and contents were evaluated in a semiquantitative fashion for the presence of granulation tissue, acute and chronic inflammation, calcium oxalate, bacteria, and fungi. The presence of fever, hemoptysis and blood neutrophilia and the results of culture of the cavity at surgery were determined by chart review. Results: Eight of the twelve cases showed bacteria within the fungus ball on histologic examination (Gram negative rods in one case; Gram positive cocci in six cases; and both Gram positive and negative organism in one). In four of these cases, foci of granulation tissue and an inflammatory exudate containing bacteria were seen on the inner surface of the cavity wall. Calcium oxalate was identified in four cases; in one, it was abundant in the cavity wall. Fungal infiltration of the wall was seen in one case. Culture of the cavity contents grew in four of the seven cases in which it was done (all four

showed bacteria on histology). There was no clear association between the presence of bacteria and either fever or neutrophilia. Conclusion: Localized bacterial infection of the cavity wall is likely to be an important cause of hemoptysis in pulmonary aspergilloma. In at least some cases, this probably originates from saprophytic colonies of bacteria within the fungus ball itself.

27

Congenital zosteriform herpes simplex infection: a case report and review of the literature

MOSA A. FAGIH, VAN H. NGUYEN, MOY FONG CHEN Pathology Department, McGill University Health Center, Montreal (Quebec), Canada Introduction: Most genital herpes simplex virus (HSV) infections are due to HSV-II. Perinatal HSV infection could be acquired through an ascending infection or by delivery through an infected birth canal. Congenital HSV infection on the other hand is a rare event. We here report a case of congenital ascending zosteriform HSV infection in a 33/52 weeks gestation baby girl. Pregnancy history: A 36-year-old G2P1 had vaginal delivery at 33 weeks gestation following premature rupture of membranes. The pregnancy was otherwise uneventful. A female baby was born weighing 2335 g with good apgar scores. Erythematous desquamative lesions were present around left thorax with a linear distribution. Erythematous maculopapular patches were also noted on the left dorsal forearm and left ventral thigh at birth. The mother had a past history of genital herpes, which was diagnosed and treated seven years ago. Her previous pregnancy a year ago resulted in a normal female baby at 36 weeks gestation with a birth weight of 2705 g. The serology status of her Herpes infection was unknown for both pregnancies and genital lesions were not noted during pregnancy or at delivery Neonatal history: Vesicles developed over the skin of the left chest wall soon after birth for which scrapings and biopsy revealed Herpes Simplex infection confirmed by immunostaining. Urine test for Cytomegalovirus was negative. Ultrasound examination of the abdomen, pelvis and head revealed hepatic calcification, bilateral hydronephrosis, and bilateral calcification of the basal ganglia, and near the lateral and third ventricles. Deformity of the left 4th, 5th, 6th and 7th ribs was noted on radiology examination. Pathology: Examination of the placenta revealed focal reactive and degenerative changes in the amnion with eosinophilic inclusion bodies in the membranes and around the cord with rare multinucleated cells. Focal chorionic necrotizing granulomatous inflammatory infiltrates with inclusions were seen. Immunohistochemical staining for HSV II and I were positive. There was absence of villitis, vasculitis or funisitis. Discussion: There are very few cases of congenital zosteriform HSV infection reported in the literature. Despite the unknown maternal serology status for HSV, our case represents an ascending HSV infection with zosteriform skin lesions as well as internal organ lesions, confirmed by skin and placental pathology.

Abstracts / Pathology – Research and Practice 200 (2004) 631–655

28

Aspergillus fumigatus pacemaker endocarditis: a rare complication of pacemaker implantation

B.R. GANNON1, R. LEONG2, T.J. CHILDS1, H. ABDOLLAH3, P.A. ISOTALO1 1

Department of Pathology and Molecular Medicine, Queen’s University, Kingston, Ontario 2 Department of Medicine, 3 Division of Cardiology, Queen’s University, Kingston, Ontario The diagnosis of fungal endocarditis is often difficult to establish and requires a high index of suspicion. Fever of unknown origin, in the setting of multiple negative blood cultures, is a common presentation of fungal endocarditis that should prompt early and serial echocardiographic examinations. Fungal endocarditis is a rare complication of pacemaker implantation that often requires aggressive surgery, including removal of all hardware, and antimycotic therapy. We describe a 71-year-old man who presented with fever of unknown origin and multiple negative blood cultures. He had a history of multiple transvenous pacemaker manipulations. He was immunocompetent. Seven weeks after a negative transthoracic echocardiogram (TTE), the patient had a repeat TTE that revealed a large mass centered around a pacemaker electrode. This mass was freely mobile between the right ventricle and the right atrium and was associated with tricuspid regurgitation. A diagnosis of culture-negative endocarditis was established and empiric antimicrobial therapy, including amphotericin B, was instituted; however, the patient developed a cerebral infarct and died. Postmortem examination revealed branched, septate fungal hyphae within a 6  3  3-cm3 pacemaker thrombus. Tricuspid and aortic valve vegetations and multiple septic emboli were identified. Postmortem cultures grew Aspergillus fumigatus. This report describes an extremely rare case of A. fumigatus pacemaker endocarditis. To the best of our knowledge, this is only the third reported case of pacemaker endocarditis due to A. fumigatus. As in many other cases, the diagnosis of fungal endocarditis was delayed in our patient and was only definitively established after postmortem examination. Early and serial echocardiograms appear vital for the early diagnosis of fungal endocarditis.

29

Sensitivity of the Pap smear for glandular lesions of the cervix and endometrium

M. MURRAY, L. GELDENHUYS Department of Pathology, Dalhousie University, Halifax, NS B3H 1V8 Objective: To investigate the sensitivity of the Pap smear for detection of adenocarcinoma in situ of the cervix (AIS), endocervical adenocarcinoma and endometrial adenocarcinoma Study methods: Computer records of the laboratory of the QE II Health Sciences Center in Halifax were searched between June 1, 1999 and May 31, 2001 for patients who had had AIS, endocervical adenocarcinoma or endometrial adenocarcinoma diagnosed on histology, as well as a Pap smear within the preceding year. The histologic and cytologic findings were correlated.

641

Results: Hundred percent of patients with AIS, 80% of patients with endocervical adenocarcinoma and 22% of patients with endometrial adenocarcinoma on histology had had positive finding on a Pap smear performed within a year of diagnosis. Conclusion: This study confirms the good sensitivity of the Pap smear for glandular lesions of the cervix, and the poor sensitivity for glandular lesions of the endometrium. It thus confirms that the Pap smear is not an effective screening tool for endometrial adenocarcinoma, and that the quest for alternative screening methods should continue.

30

The Dalhousie university medical humanities program

LAURETTE GELDENHUYS Departments University

of

Pathology

and

Medicine,

Dalhousie

Objectives:

 To describe the Dalhousie University Medical Humanities Program.

 To show that the program is successful in its goals.  To demonstrate the importance of the Medical Humanities in medical education. In his article ‘‘Why the Medical Humanities’’ (http://humanities.medicine.dal.ca/why.html), Dr. T.J. Murray, Director of the Dalhousie University Medical Humanities Program states that the humanities have always been part of medical education in the past. He stresses that ‘‘the central importance of the humanities in medical education must be addressed consciously and not just taken for granted as something that will be there, or will necessarily follow from a science-based biomedical curriculum.’’ He points out that ‘‘the humanities help us understand the nature and values of science through ways of exploring and thinking and learning that are appropriate to the humanities.’’ I describe the Dalhousie University Medical Humanities Program using my personal experience of the program, the report of a committee which recently reviewed the program, discussions with Dr. Murray, and literature produced by the program. I also comment on a survey in the report on the extent and importance of the program in the medical community. I conclude that the Dalhousie University Medical Humanities Program is an example of successful integration of the Medical Humanities in the life of a medical school, and that review of the program illustrates the importance of the Medical Humanities in medical education.

31

Alexander Meisels

LAURETTE GELDENHUYS Departments of Pathology University, Halifax

and

Medicine,

Dalhousie

There are few that would argue that Alexander Meisels is one of the most important figures in the history of Canadian

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Abstracts / Pathology – Research and Practice 200 (2004) 631–655

cytopathology. Of his elucidation of the role of the human papilloma virus in cancer of the cervix, Bernard Naylor stated that it was ‘‘. . . probably the most important in the field of gynecological cytopathology since the introduction of cytology as a diagnostic tool.’’ (B. Naylor, The century for cytopathology, Acta Cytol. 44 (2000) 709–725.) This article tells the story of a brilliant man, a victim of Nazi persecution, who overcame many difficulties, and experienced a series of happy coincidences, to be launched into a glorious career in Cytopathology. It relates the fascinating detective story of his investigation of the nature of the koilocyte. Initially the publications of Meisels and coworkers were met with great skepticism, but with time the importance of their discovery became widely recognized. While possibly his most important contribution to cytopathology is the identification of the koilocyte with HPV infection, he has numerous other accomplishments, recognized in his adoptive country by awards such as the Order of Canada and the William Boyd Lectureship from the Canadian Association of Pathologists. His enormous contribution to cytopathology has also been acknowledged outside Canada by numerous accolades, including two honorary doctorates.

32

Evaluation of c-kit expression in small cell lung carcinoma: a validation study

R. GEORGE, K.F. KWAN, C.M. MCLACHLIN, M.M. WEIR Department of Pathology, London Health Sciences Center & University of Western Ont., London, Ont., Canada Background and objectives: Recently, c-kit has been recognized as a new prognostic marker in small cell lung carcinoma (SCLC), with hope that Gleevac (a c-kit receptor antibody) may impact patients with poor chemotherapy responses. The purposes of this study are: (1) to evaluate the frequency of c-kit expression by SCLC and (2) examine the reproducibility of ckit expression interpretation by different observers. Methods: We retrospectively selected 27 cases of SCLC from our files (25 bronchial biopsies, 2 lymph nodes). All diagnoses were confirmed by one of the authors. The formalin-fixed, paraffin-embedded tissue was stained with polyclonal antibody to c-kit (DAKO). The staining was scored semi-quantitatively by 4 blinded observers as follows: intensity—0: none; 1þ: weak and 2þ: strong; and percentage of stained cells—0%, 1–50% or 4 50%. The observers were shown standardized slides prior to scoring. Results: All observers agreed that 21/27 (78%) SCLC showed positive c-kit staining. In the other 6 cases, 1–3 observers noted absent staining, and the others noted weak ð1þÞ staining. Most observers agreed that 13/27 (48%) SCLC showed 4 50% cell staining for c-kit and 6/27 (22%) showed 1–50%. C-kit staining was noted to be negative in areas of tumor crush artifact. Conclusions: In this study, a high number of SCLC showed ckit expression. Pitfalls were: (1) c-kit positive staining interpretation is observer dependent, even after standardization; and (2) the quantification of c-kit-stained cells may be underestimated due to negative c-kit staining in crushed tumor cells.

33

Congenital midline spinal hamartoma in a neonate: a case

report R.S. GOSWAMI, S. ALBRECHT, J.L. MONTES, C. BERNARD Departments of Pathology and Neurosurgery, Montreal Children’s Hospital, McGill University, Montre´al, Que´bec, H3Z 3B8 Congenital midline spinal hamartoma is a rare entity. We report the case of a 1-week-old neonate with progressive quadriplegia and clinical evidence of an intra- and epidural tumor extending to the cervical paravertebral region and the right brachial plexus. The child also has a cutanous hemangioma of the right upper arm. The tumor was excised and demonstrated a haphazard arrangement of well-differentiated, mature, mesenchymal and neuroectodermal elements normally found within the spinal and paraspinal regions. It consisted of islands of mature cartilage surrounded by a stroma containing small- and medium-sized vessels, with interspersed mature ganglion cells, as well as nerves. None of the cells within the lesion exhibited atypical features, and no endodermal or epithelial components were seen. Midline spinal hamartoma must be distinguished from a teratoma since the prognosis of each entity is different. Previously reported spinal hamartomas arose in the thoracic, lumbar, or sacral regions. They contain local, well-differentiated, homologous mesodermal and ectodermal elements arranged in a disorganized manner without the potential for excessive growth or malignant degeneration. They were not associated with spinal dysraphism but some patients had associated cutaneous hemangiomas. Teratomas, by comparison, are composed of mature or immature derivatives of all three germ cell layers and may be associated with spinal dysraphism. They are located either within the spinal canal or the sacrococcygeal region and are known to have the potential for malignancy, emphasizing the need to distinguish them from spinal hamartomas. The unique feature of this case is the presentation of a rare lesion in an unusual location. No such case in a neonate has previously been reported.

34

p16 Immunohistochemistry in glial tumors

PETER GOULD, LE´O CANTIN, CLAUDE PICARD, DANIEL LACERTE, ANDRE´ TURMEL CHA Hoˆpital de l’Enfant-Je´sus, Quebec City, QC, Canada The p16/RB/CDK4 cell-cycle regulatory pathway is frequently disrupted in high-grade gliomas. Deletions of chromosome 9p21, which eliminate the CDKN2A gene encoding p16, are particularly well characterized, and are associated with shortened median patient survival. Although most glial tumors fail to stain on immunohistochemistry for p16, upto 20% of high-grade glial tumors show p16 immunopositivity, so it has been suggested that p16 immunohistochemistry could serve as a screening assay to direct further molecular studies and identify tumor subgroups. In order to assess whether p16 immunostaining can identify tumor subgroups in surgical neuropathology practice, a series of 25 glial tumors (6 low grade, 19 high grade) operated at this

Abstracts / Pathology – Research and Practice 200 (2004) 631–655

institution between September 2003 and January 2004 were examined for p16 immunoreactivity using commercially available mouse monoclonal antibodies known to be specific for p16 (Chemicon MAB4133 and MAB88057). Both antibodies showed similar patterns of immunoreactivity. We confirmed that normal brain matter shows virtually no staining for p16, and that most high grade glial tumors lack evidence of p16 expression. Nevertheless, nuclear and cytoplasmic staining for p16 was present in 5 of 25 glial tumors, including 3 of 14 glioblastomas. These findings are similar to those of Burns et al., and support the use of p16 immunohistochemistry as a practical screening procedure.

35

Les le´sions a` cellules fusiformes de la prostate: analyse clinico-pathologique de 17 cas KATHERINE GRONDIN, BERNARD TEˆTU Service d’anatomo-pathologie, Que´bec, Universite´ Laval

CHUQ

L’Hoˆtel-Dieu-de

Introduction: Les le´sions stromales prostatiques sont des entite´s rares dont la terminologie et l’e´volution font l’objet de confusion dans la litte´rature. Le spectre des le´sions rapporte´es varie de le´iomyome be´nin aise´ment identifiable a` une tumeur phyllode, une entite´ tre`s rare au potentiel malin plus difficilement appre´ciable. Quelques cas rapporte´s font e´tat de le´sions pseudo-sarcomateuses interpre´te´es initialement comme malignes et donc traite´es aggressivement. L’interpre´tation de ces le´sions est complique´e par l’absence de classification simple et claire dans la litte´rature. Mate´riel et me´thode: Afin d’e´tablir une classification simple et de de´finir des crite`res de mauvais pronostic, nous avons analyse´ 17 cas de le´sions a` cellules fusiformes de la prostate observe´es dans notre milieu ou e´value´es en consultation au cours des 15 dernie`res anne´es. La pre´sentation clinique, l’e´volution et les caracte´ristiques histologiques ont e´te´ compare´es. Re´sultats: Les re´sultats obtenus nous permettent de proposer une classification en 2 groupes selon la pre´sence ou l’absence de glandes suivie d’une subdivision de chacun de ces groupes en 3 sous-groupes selon le degre´ d’atypies cytologiques. Parmi les le´sions e´value´es, 11 e´taient clairement be´nignes, 3 pre´sentaient un caractere malin alors que les 3 autres e´taient de potentiel malin incertain. Dans tous les cas, les crite`res permettant de se prononcer en faveur d’une malignite´ e´taient :un nombre de mitoses supe´rieur ou e´gal a` 5 par 10 grands champs (40X) et la pre´sence de ne´crose. De plus, tous les cas combinant une prolife´ration e´pithe´liale et stromale prenaient l’aspect d’une tumeur phyllode. Conclusion: Cette e´tude propose une classification simple des le´sions a` cellules fusiformes de la prostate qui devrait aider a` les reconnaiˆtre et ainsi e´viter que des traitements radicaux soient institue´s inutilement.

36

A study of enzyme immunoassay (EIA) for antiextractable nuclear antigens (ENA) using recombinant versus native proteins

A.K. GUHA, S.K. MURRAY

643

Department of Pathology, QEII Health Sciences Center, Capital Health and Dalhousie University, Halifax, Nova Scotia Recombinant proteins are replacing native ones in many enzyme immunoassays (EIAs) but epitopes may have altered reactivity with natural antibodies observed in autoimmune disorders. We tested 91 sera with new kits for the detection of anti-extractable nuclear antigens (ENA) using recombinant SS-B and SS-A 52 kDa, Scl-70 and Jo-1 with purified native human snRNP/Sm, Sm, and SS-A 60 kDa. Anti-nuclear antibody (ANA) was also determined with a screen EIA and an immunoflourescence assay (IFA) using lysed and cultured HEp2 cells as substrates, respectively. A 1:100 dilution for all assays and a fully automated 96 well microtiter machine with plate reader capability at 450 nm was used. Twenty-six of 91 sera were negative for ANA by IFA. Nineteen of 26 were negative in all EIAs. Six of 26 were positive with the EIA screen for ANA and with one or more specific anti-ENA EIAs (SS-A and/or snRNP/Sm). Five of 6 were positive for antinative-SS-A. However, only 3/6 were positive with the antirecombinant-ENA screen. Three of 91 were positive for antiJo-1 and only 1 was positive for anti-Scl-70 but all 4 sera were positive with EIA screens for ANA and anti-ENA and negative with the specific EIAs for other ENAs. Sixteen of 61 specimens that were ANA positive by IFA, had low (e.g. 1:100) IFA titer and negative EIA screen for ANA. Fourteen of 61 had significant differences between native and recombinant kits. Ten of 14 specimens had discrepancies involving SSA and SS-B. Furthermore, 6/26 ANA negative sera by IFA also had positive anti-ENA. All 6 had mismatched results with native and recombinant kits with an SS-A abnormality in 4. Finally, 9/61 ANA positive specimens and 3/26 ANA negative specimens had different anti-ENA screens than the specific anti-ENA EIAs. Eleven of 12 of these specimens had a negative anti-ENA screen, which was coupled to a positive specific anti-ENA. We conclude that (1) there is a difference in reactivity of anti-ENAs to native and recombinant proteins and (2) the screening recombinant EIA kit is less sensitive than the specific EIA kit.

37

Frequency of hyperplastic polyp-like morphology (serrations) in sporadic large bowel adenomas S. SERRA1,2, M. GUINDI2, R. H. RIDDELL2 1

University of Italy Department of Laboratory Medicine and Pathobiology, University of Toronto 2

The serrated neoplasia pathway refers to progression of colorectal neoplasms that involves hyperplastic polyps (HP) and/or serrated adenomas (SA). The definition and frequency of SA in the literature is not clear. Serrations may also be found in sporadic adenomas if searched for. Purpose: To determine the frequency of serrated architecture in adenomas and HP, the percentage of serrated glands, the degree of serration, and to correlate these features with grade of dysplasia and size in adenomas. Methods: Eighty-four randomly selected colorectal adenomas and 20 HP were analyzed. The number of serrated crypts in each polyp was counted and expressed as a percentage of the

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total number of crypts. The degree of serration was graded on a scale of 0–3 (0, no serration; 1, minimal serration identified upon careful scrutiny; 2, moderately easy to recognize; 3, marked or florid). Dysplasia was graded as high or low grade. The highest grade of dysplasia in the serrated and nonserrated areas in the polyps was recorded separately. Results: Serration of any degree was found in 76% of all adenomas and their degree increased with size (see table). Serration was present in o 10% of the glands in 78% of all adenomas and in 4 10% in 22%. 19/20 HP (0.2 to o 2 cm) showed grade 3 serration, and the other grade 2. There was no clear correlation between grade of dysplasia and serrations. Conclusions: Serrated crypts are common in adenomas. The frequency of serration increases with size, being present in 90% of adenomas 4 5 mm. Grade 2/3 serrations were common in large ð4 2 cmÞ adenomas. The opportunity for a serrated neoplastic pathway to be expressed appears to exist in most adenomas:

Segmental mastectomy revealed a well-circumscribed, 5  5  5-cm3 mass with large clefts and areas that grossly resembled adipose tissue. Microscopy revealed a high-grade malignant phyllodes tumor characterized by stromal cell overgrowth, prominent nuclear pleomorphism, extensive mitotic activity and foci of tumor necrosis. In addition, pleomorphic liposarcomatous differentiation was identified and consisted of uni- and multi-vacuolated hyperchromatic lipoblasts. This tumor was completely excised and the patient remains disease free 16 months after surgery. The medical literature concerning the rare occurrence of heterologous sarcomatous differentiation in phyllodes tumors is reviewed.

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Calretinin selectivity for ganglion cell staining: a new tool for diagnosing Hirschsprung disease?

W. JO, F. MOTHAFAR, O. BOUTROSS TADROSS Size (cm)

o 0:5 0.5–1.0 4 1:0–2:0 4 2:0

Number

26 23 28 7

Grade of Serration 0

1

2

3

14 0 6 0

10 21 18 0

2 0 2 4

0 2 2 3

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Pleomorphic liposarcomatous differentiation in a malignant phyllodes tumor: a case report and review of the literature

P.A. ISOTALO1, R.L. GEORGE2, R. WALKER2, S.K. SENGUPTA1 1 Department of Pathology and Molecular Medicine, Queen’s University, Kingston, Ontario 2 Department of Surgery, Queen’s University, Kingston, Ontario

Phyllodes tumors (PT) are uncommon fibroepithelial breast neoplasms that may be classified as benign, low-grade malignant or borderline, and as high-grade malignant tumors. High-grade malignant PT are characterized by invasive tumor borders and commonly demonstrate hypercellular stromal overgrowth, stromal cell nuclear pleomorphism and high stromal proliferative activity. Rarely, malignant PT contain heterologous sarcomatous elements. The proper classification of PT is important as both low-grade and high-grade malignant PT have metastatic potential. All PT have potential for local recurrence, especially if incompletely excised. This report describes a 47-year-old woman who was diagnosed with a rare, high-grade malignant phyllodes tumor that demonstrated liposarcomatous differentiation. The patient had a 1-year history of an asymptomatic, left upper outer quadrant breast mass that had increased in size over a 5-month period. No axillary lymphadenopathy was present. The contralateral breast contained no palpable abnormalities. The patient had no significant past medical history. There was no family history of breast carcinoma.

Diagnosis of Hirschsprung’s disease relies on pathologists’ expertise on H&E and special stains such as acetylcholinesterase, S100 and PGP 9.5. Acetylcholinesterase must be performed on frozen tissue, when it stains muscle fibers, and in the presence of hemorrhage, will stain diffusely. Immunohistochemical stains such as S100 and PGP 9.5 usually show nonspecific background staining. Fortunately, while performing special immunostains on a peritoneal cyst we found out that calretinin immunostain selectively demonstrated ganglion cells. Method: Hirschsprung cases between 2001 and 2003 at HHSC McMaster site were screened. Biopsy and resection cases were randomly chosen, and Calretinin stain was performed and was qualitatively compared to cholinesterase, S100 and/or PGP 9.5. The staff pathologist and one of the two residents reviewed the slides. Results: In all the cases, Calretinin selectively stained ganglion cells which were highlighted without background staining and were well demonstrated in patients as young as one day old. In comparison, the other immunostains were nonspecific to the ganglion cells and stained the blood vessels, muscle fibers and nerve fibers. Conclusion: Considering these results, Calretinin is a useful stain in diagnosing or ruling out Hirschsprung’s disease. Also, considering the observation that the number of ganglion cells varied according to region, the selectivity of this immunostain will allow further quantitation of the ganglion cells by morphometric studies in a larger scope to determine normal variability of the numbers of ganglion cells according to age and region of the intestine.

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Synchrotron infrared spectral mapping of a metastatic lymph node

TOMMY H. LEE 1, RANI KANTHAN 1, BERNHARD JUURLINK1, KATHLEEN M. GOUGH 2 1

College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada 2 Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, Canada

Abstracts / Pathology – Research and Practice 200 (2004) 631–655

Background: Infrared (IR) spectral mapping is a nondestructive technique, which employs the spectroscopic features of a sample to construct an image, revealing information about the chemical composition of a tissue. The emergence of IR spectroscopy with a synchrotron source has allowed resolution of details in the order of microns that can be compared to traditionally stained sections. Design: Formalin-fixed, paraffin-embedded section of a lymph node containing metastatic colonic adenocarcinoma was mounted on a MirrIR (Kevley Technologies), IR-reflective slide. This section was analyzed at the National Synchrotron Light Source (Brookhaven, NY) on the U10B IR microspectroscopy beamline. Spectral data were collected at a spatial resolution of 10 mm and a spectral resolution of 4 cm1 . Data analysis was accomplished with the Nicolet OMNIC and Atlus spectral mapping software. Spectral maps were compared to traditional stained sections. Results: A variety of spectral maps were constructed for our sample. IR signals from various functional groups belonging to lipid, protein, collagen and other basic cellular constituents allowed us to differentiate normal lymph node tissue from metastatic colonic tissue. This suggests that the malignant degeneration of a lymph node is reflected in changes of its spectra, which in turn reflects changes in the levels of its basic constituents. Conclusion: IR spectral mapping is a highly flexible, nondestructive technique, which, from a single data collection, allows simultaneous imaging of many aspects of the functional group composition of a tissue. We have been able to define structural features and differentiate normal from abnormal tissue. The value of IR spectroscopy with synchrotron as a research tool has already been well established; however, its value as a diagnostic tool is still being elucidated. Further samples are being analyzed to validate our preliminary pilot findings.

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Is transmural inflammation in the ileoanal pouch significant?

K.N. MACNEILL1, R.H. RIDDELL2, R. MCLEOD2, M. GUINDI3 1

Department of Pathology, University of Toronto, Toronto, Ontario 2 Mount Sinai Hospital (MSH), Toronto, Ontario 3 University Health Network, Toronto, Ontario Background: Ileal pouch anal anastomosis is the operation of choice for ulcerative colitis (UC) patients after colectomy. When pouches are excised due to complications or failure, the question of underlying Crohn’s Disease (CD) is often raised. Transmural lymphoid aggregates (TLAs) are an accepted feature of CD, yet their significance in the excised pouch is not known. Design: One hundred and two excised pouches were identified from the Inflammatory Bowel Disease (IBD) database at MSH from 1983 and 2002. Slides from the excised pouches and the corresponding colectomies were obtained for review while blind to the initial pathologic diagnosis and subsequent clinical follow-up. Pouches were evaluated for 26 histological parameters, including TLAs. Clinical follow-up was obtained from the IBD database.

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Results: Slides from 82/102 excised pouches were reviewed. TLAs were identified in 36/82 pouches. Pre-op diagnosis was UC in all cases. Colectomy slides were reviewed for 22/36 patients. This review revised 8UC diagnoses to 2 CD, 5 indeterminate colitis (IC), and 1 non-specific fulminant colitis. The 22 reviewed diagnoses were compared to the current clinical database diagnoses (based on pathology/clinical evolution) resulting in a final diagnostic breakdown of 20 UC, 12CD and 4 possible CD (?CD). TLA occurred in all sites (proximal &distal margins/efferent &afferent loop/anastomosis/blind) of the pouch, most commonly in the reservoir (28/ 36):17 UC, 8 CD,3 ?CD). The distribution of TLAs in the remaining sites was similar. Conclusion: Since transmural inflammation was seen in all parts of the pouch in both UC and CD, this finding in the excised pouch is not specific for or diagnostic of CD in the pouch. It is insufficient to change the classification of the underlying IBD from UC to CD.

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New lung carcinoma antibody ES1: an immunohistochemical study of sensitivity and specificity

KIEN T. MAI1, D. GARTH PERKINS1, JIANBING ZHANG2, C. ROGER MACKENZIE2 1 Department of Pathology and Laboratory Medicine, The Ottawa Hospital, Civic Campus and University of Ottawa, Canada 2 Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ont., Canada

Background: A monomeric heavy chain antibody, AFAI, was produced by panning a naı¨ ve phage display library of single domain antibodies (derived from the heavy chain antibody repertoire of a llama) against the non-small cell lung carcinoma cell line A549. The AFAI phages were isolated and the AFAI gene was then sequenced. The new antibody ES1, a pentameric form of AFAI was produced by fusing AFAI and the B subunit of verotoxin, a self-pentamerizing domain. The AFAI antigen was identified as a variant of CEACAM6 known to be present in a wide range of normal tissue and involved in neoplastic progression of colonic adenomas and carcinomas. Design: Various normal tissues and 119 neoplastic lesions from lung colon, breast and other organs were immunostained for ES1 using the ABC technique Results: ES1 showed positive immunostaining ranging from slight to moderate in 23 and strong immunoreactivity in 10 of 35 non-squamous large cell carcinomas. The two tumors which were not immunoreactive were a large cell undifferentiated carcinoma with some squamous features and a non-mucinous bronchiolo-alveolar carcinoma. Colonic adenocarcinomas and invasive duct carcinomas of the breast showed a weak-tomoderate immunoreactivity in 9 and strong immunoreactivity in one of 23 tumors. The other carcinomas and all normal tissues with or without an adjacent carcinoma were not immunoreactive Conclusions: Unlike other CEACAM6 antibodies, ES1 can be used as a marker for lung adenocarcinoma due to the negative immunoreactivity for normal tissues. ES1 tends to be more immunoreactive with the poorly differentiated than the welldifferentiated adenocarcinoma. The antibody showed some

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cross-immunoreactivity with colonic and breast carcinomas. For these cancers, the immunoreactivity was more focal and weaker than for lung adenocarcinoma.

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C-kit protein expression in adenoid cystic carcinoma of the breast

C. MATTE1, D.W. VISSCHER2, C. REYNOLDS2 1

Charles Lemoyne Hospital, Greenfield Park, Quebec Mayo Clinic, Rochester, Minnesota

2

Background: C-kit protein is a membrane-bound tyrosine kinase receptor and protein overexpression has been noted in several neoplasms. Recent reports have suggested that c-kit protein overexpression is involved in the pathogenesis of adenoid cystic carcinoma (ACC) of the salivary gland. However, c-kit expression has not been previously studied in ACC of the breast. Design: Twenty-four cases of ACC of the breast were identified in our surgical pathology consultation files from 1994 to 2003. Formalin-fixed, paraffin-embedded archival tissue from all cases was immunostained with a polyclonal antibody against c-kit protein (DAKO, 1/600 dilution). Antibodies against keratin (AE1/3), smooth muscle actin and vimentin were also applied to characterize these tumors. The avidin–biotin–peroxydase complex detection method was utilized. Cases were scored as 1+ (1–25% positive), 2+ (26–50% positive) and 3+ (4 50% positive). As controls, tissue microarrays were constructed with representative cores from 97 breast cancers and immunostained with anti-c-kit antibody. Results: All 24 cases of ACC of the breast showed c-kit expression (3+, 13 cases; 2+, 8 cases; 1+, 3 cases). C-kit expression was associated with the epithelial component of the ACCs (keratin positive cells) but not with the myoepithelial component (smooth muscle actin, vimentin positive cells). Overall, the c-kit staining pattern was identical to the keratin staining pattern in these tumors. C-kit expression was rare (1/97 breast cancers) in the control tissues. Conclusion: C-kit protein is expressed in ACC of the breast. The staining pattern of c-kit is distinctive and correlates with the presence of an epithelial phenotype. A potential role for ckit as a new therapeutic target in the treatment of patients with metastatic ACC should be further investigated.

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What is the best method to determine anatomic pathology workload? Canadian experience

RAYMOND T. MAUNG Laboratory, Royal Inland Hospital, Kamloops, BC V2C 2T1 Context: Health Care Resources in Canada are limited, and there is tremendous pressure to reduce laboratory budgets. It is almost impossible to acquire new pathologist positions to adequately meet service demands. There is a need to determine objectively an appropriate pathologist’s workload. Objectives: To look at multiple indicators that may reflect pathologist’s work and determine which indicator(s) is the best.

Design: Two inter-related surveys; the first canvassed the opinions of working pathologists in Canada as to what pathologist activities should be counted, and how to best measure these. Based on the first survey, the second survey requested detailed information in relation to the various indicators that may be useful to determine pathologist’s workload. Results: Forty-three respondents in the first survey: pathologist’s activities divided into (1) consultation, (2) administration, and (3) professional development/academic activities. Weighting of the different types of consultations was determined. Administrative needs were determined by the complexity of the department, and professional development/ academic activities by relative-time commitment. Twentyseven respondents on the second survey, the different indicators were analyzed using different statistical routines. Of all the indicators analyzed, Level 4 equivalent has the highest R2 value of 0.994 and the lowest P value. It is a direct output measurement of pathologist’s consultations and uses data that is routinely collected in many North American laboratories. Conclusions: Level 4 equivalent is the best indicator to measure anatomic pathology consultative activities.

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Primary localized amyloidosis of the lower genitourinary tract: a case series of nine patients J. MERRIMEN, R. GUPTA Division of Anatomic Pathology, Dalhousie University, Halifax, NS Purpose: Primary localized amyloidosis of the lower genitourinary tract is a rare condition. In this study we evaluate the presentation and prognosis of this entity and perform histochemical and immunohistochemical stains to identify the type of amyloid deposited. Patients and methods: A computer-based search was performed to identify patients diagnosed with amyloidosis of the ureters, urinary bladder or urethra from 1976 to 2003 at the QEII Health Sciences Center. The medical records were reviewed and histochemical stains for amyloid and immunohistochemical stains were performed. Results: Eight cases of amyloidosis of the urinary bladder and one case of amyloidosis of the renal pelvis and ureters were identified. The median age of the 5 male and 4 female cases was 72 years. Of the cases with amyloidosis of the urinary bladder, 5 cases (62%) presented with gross hematuria, 1 case presented with irritative symptoms and 2 cases were detected during follow-up for other genitourinary conditions. The patient with amyloidosis of the renal pelvis and ureter presented with flank pain and gross hematuria. Cystoscopic impression was that of neoplasia in six cases (75%). Two patients (25%) with urinary bladder amyloidosis had symptomatic recurrences. All cases stained positive with histochemical amyloid stains and all showed retention of congophilic staining when treated with potassium permanganate, consistent with primary localized amyloidosis. Immunohistochemical stains revealed 7 (78%) cases to be lambda light chain-restricted and 2 (22%) cases to be indeterminate. Conclusions: Primary amyloidosis of the lower genitourinary tract is a rare condition which mimics carcinoma in presentation

Abstracts / Pathology – Research and Practice 200 (2004) 631–655

and is cystoscopic appearance. The majority of cases appear to represent AL amyloid deposition. Recurrences occur and followup is required.

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Expression of the intermediate filament neurofilament (NF) within uterine malignant mixed mullerian tumor (MMMT)

S.K. MURRAY1, R.N. GRIMSHAW2, J. BENTLEY2, A.K. GUHA1 1 Department of Pathology, QEII HSC, Capital Health and Dalhousie University, Halifax, NS Canada 2 Division of Gynecologic Oncology, QEII HSC, Capital Health and Dalhousie University, Halifax, NS Canada

In routine practice, we have noticed individual cases exhibiting areas suspicious for neural/ganglionic and glial differentiation which showed expression of NF. This prompted us to undertake a study of 15 consecutive MMMTs that were diagnosed and treated at our Institution. An average of 2 blocks were selected from each case to include both epithelial and mesenchymal areas including zones with heterologous differentiation. Immunostaining for the following proteins was carried out on sections from the selected blocks using an automated staining unit (NexesTM and BenchmarkTM modules, Vantana Medical Systems); NF, desmin, chromogranin, C-kit ligand, Mic-2, GFAP, PLAP, synaptophysin, S-100, HPL, AFP, HCG, keratin (AE1/AE3), vimentin, ER, E-cadherin and p53. The percentage of cases positive for each marker are as follows: NF 46.7 (7/15), GFAP 80 (12/15), synaptophysin 33.3 (5/15), Mic-2 33.3 (5/15), S-100 20 (3/15), C-kit ligand 33.3 (5/15), chromogranin 6.7 (1/15), PLAP 0 (0/15), HPL 6.7 (1/15), AFP 13.3 (2/15), HCG 0 (0/15), keratin 100 (15/15; 15/15 carcinomatus component, 7/15 focally in sarcomatous component), vimentin 100 (15/15; 8/15 focally in carcinomatous component 15/15 in sarcomatous component), desmin 40 (6/15; 1/6 focally in carcinomatous component; 6/6 in sarcomatous component), ER 46.7 (7/15), E-cadherin 53.3 (8/15), and p53 80 (12/15). Of the 7 cases which demonstrated NF positivity in 5 (71%), there was focal strong positivity within carcinomatous components and in four (57%) there was focal positivity in sarcomatous components. This report demonstrates the expression of a very restricted intermediate filament, NF, in MMMT.

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A variant of endometrioid carcinoma (EC) of the uterine corpus with hyalinization, sex cord-like formations and other unusual morphologic features S.K. MURRAY1, P.B. CLEMENT2, R.H. YOUNG3,4 1

Department of Pathology, Dalhousie University, Halifax, NS, Canada 2 Department of Pathology, VHHSC, UBC, Vancouver, BC, Canada 3 The James Homer Wright, Pathology Laboratories of the Massasschuetts General Hospital, USA 4 Department of Pathology, Harvard Medical School, Boston, MA, USA

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We describe a series of unusual endometrioid carcinomas (ECs) of the uterine corpus with frequent cords, spindle cell growth and a hyalinized stroma, which sometimes underwent osseous metaplasia [‘‘corded and hyalinized EC’’ (CHEC)]. Cases were identified by searching the consultation files of one of the authors (RHY) and Dr. R.E. Scully. The patients ranged in age from 25 to 83 years (mean—52 years). The proportion within each stage was: stage IA—9.7% (3/31), stage IB—45.2% (14/31), stage IC—9.7% (3/31), stage II— 16.1% (5/31) [all exhibiting cervical stromal invasion—stage IIB], stage IIIC—3.2% (1/31) and stage IV—3.2% (1/31)[12.9 (4/31) not staged]. No high-grade nuclear atypia was seen in any case of CHEC, the majority being nuclear grade II (20/31, 64.5%) and the remainder being nuclear grade I (11/31, 35.5%). Vascular space invasion was identified in seven tumors (7/31, 22.6%). Twenty-two tumors (22/31, 71%) exhibited squamous differentiation and 16 had background endometrial hyperplasia (16/31, 51.6%). On immunohistochemical analysis the EC component was strongly positive for keratin. Keratin exhibited more focal and variable staining in the corded and hyalinized areas. Desmin, actin, CD10, and inhibin were negative in CHEC. Over-expression of p53 was found in only one case (3.2%). Eighty-three percent of patients were alive with no evidence of disease on follow-up (2–115 months, mean—34.4 months). CHEC is a distinctive variant of EC, typically low stage (74% stage I), has a generally good prognosis, and should be distinguished from MMMT to avoid more aggressive treatment than is indicated.

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Hyaline sclerosis of the renal vasa recta: an underappreciated lesion

M.Y. NGAE1, R. LOUTZENHISER2, H. BENEDIKTSSON1 1

Department of Pathology and Laboratory Medicine, Foothills Medical Center 2 Department of Pharmacology and Therapeutics, University of Calgary, Alberta, Canada, T2N 2T9, Background: Vasa recta arise from the efferent arterioles of juxtamedullary glomeruli. They perfuse the salt-transporting epithelia of the loop of Henle and collecting ducts, and are believed to be the primary site of differential regulation of the medullary circulation. Pathological abnormalities in the vasa recta are rarely described, mostly related to systemic vasculitis. Sporadic observations of vasa recta hyaline sclerosis (VRHS) in biopsies from patients with focal glomerulosclerosis (FSGS) and renal transplants prompted this study. Materials and methods: We examined 52 renal biopsies from patients with FSGS, diabetic nephropathy, hypertensive nephrosclerosis, chronic allograft nephropathy (CAN), cyclosporin toxicity, and glomerulonephritis. Sixteen cases were rejected due to inadequate medullary sampling. The biopsies were scored semi-quantitatively for VRHS as well as glomerulosclerosis, arterial fibrointimal thickening, arteriolar hyalinosis, tubular atrophy, cortical and medullary fibrosis. Results: VRHS was found in FSGS (5/12), DM (2/6), CAN (2/5), CyA toxicity (1/2). Biopsies from patients with nephrosclerosis (2), glomerulonephritis (2) showed no VRHS. Two of 7 protocol transplant biopsies showed VRHS, one from a diabetic patient; the other patient had FSGS as the original disease.

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Conclusions: An association may exist between VRHS and FSGS, chronic allograft nephropathy, calcineurin-inhibitor toxicity and diabetic nephropathy. It can occur before other vascular or parenchymal lesions. Increased transmitted pressure is a likely mechanism, however, toxic drug effects and post-inflammatory scarring may also play a role. VRHS is an under-recognized lesion and may have significant functional correlates.

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Mutational analysis of metastatic GI stromal tumors

J. PARFITT, S. CHAKRABARTI, D.K. DRIMAN Department of Pathology, London Health Sciences Center and the University of Western Ontario, London, Ont., Canada N6A 5A5 Background: Gain of function mutations in exons 9 and 11 of the c-kit proto-oncogene occur in GI stromal tumors (GISTs). The liver is the commonest site for metastases. Aim: To characterize GISTs metastatic to liver according to morphologic features and mutational activity in exons 9 and 11. Methods: Two gastric and two small intestinal GISTs metastatic to the liver were evaluated. The primary tumors were assessed for risk of aggressive behavior using morphologic criteria. Immunohistochemistry for KIT, CD34, desmin, muscle-specific actin, smooth muscle actin, S100, and vimentin was performed. Mutational analysis was performed on exons 9 and 11 of c-kit by PCR amplification and direct gene sequencing. Results: All primary tumors were morphologically similar to the metastases. Two gastric and one intestinal GIST were of high risk for aggressive behavior. The remaining tumor was of intermediate risk; all were positive for KIT. One intestinal tumor had mutations in exon 9 (3 point mutations: codons 507, 509) only in an intrabdominal recurrence. The other intestinal GIST showed mutations in exon 11 (6 point mutations: codons 564–575, 6 bp in-frame deletion of 571ATA and 572GAC) only in the primary. One gastric case had up to 11 point mutations in exon 11; the primary showed a single point mutation in codon 583, also present in the metastasis along with 10 additional point mutations between codons 559 and 590. The other gastric tumor and its metastasis had no mutations. Conclusions: The presence of exon 9 mutations in recurrent tumor only suggests that these mutations may mark aggressive behavior. The paradoxical presence of exon 11 mutations in a primary GIST and absence in its metastasis suggests that increasing mutational burden in this exon may not correlate with metastatic potential.

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Cervicovaginal (Papanicolaou) smear findings in uterine adenosarcomas S. PASTERNAK, R.F. MACINTOSH Division of Anatomic Pathology, Dalhousie University, Halifax, Nova Scotia Purpose: Adenosarcoma is a rare uterine biphasic tumor composed of benign epithelial elements and a sarcomatous

stroma. Although it is well described histologically, its cytological features are rarely mentioned in the literature. The purpose of this study was to investigate Papanicolaou (Pap) smear findings in patients diagnosed with adenosarcomas. Methods: A computer-based search was performed for surgical pathology records of all patients diagnosed with uterine adenosarcoma at the Queen Elizabeth II Health Sciences Center from July 1998 to July 2003. Patients who had Pap smears within 6 months prior to the surgical resection of the tumor were included in this study. Surgical resection specimens and medical records were reviewed. Pap smears were rescreened by the authors. Results: We identified 5 patients diagnosed with adenosarcoma with Pap smears performed prior to the resection. Four patients presented with polyps and one of them proved to have extension into the lower uterine segment and cervix. In 3 patients the Pap smear revealed the presence of abnormal mesenchymal cells. In one patient, although possible abnormal groups of cells were noted, evaluation was limited by marked degeneration. One patient had a negative pap smear. Conclusion: Pap smears were able to show changes related to the presence of an underlying uterine adenosarcoma in 3 of the 5 patients. When spindle cells are noted in a cervicovaginal smear, mesenchymal lesions, such as adenosarcoma, should be considered in the differential diagnosis.

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Second surgery after conservative breast excisions

S. PASTERNAK1, L. HELYER2, C. GIACOMANTONIO2, P. BARNES1 1

Division of Anatomic Pathology, Dalhousie University, Halifax, Nova Scotia 2 Department of Surgery, Dalhousie University, Halifax, Nova Scotia Purpose: The standard care regarding conservative surgery for invasive and in situ breast cancer is to obtain clear resection margins. The incidence of re-operation due to close or positive margins varies widely in the literature (4–45%). A retrospective study was carried out in our center to determine our experience and to compare the rates of re-operation between palpable lesions and radiologically detected breast cancers excised with the help of hook wire localization. Methods: A computer-based search was performed for surgical pathology records of all patients who underwent a breast core biopsy at the Queen Elizabeth II Health Sciences Center in 2000 and 2001. Positive core biopsies pathology records were reviewed. Data collected included initial tumor type and grade, volume of tissue excised, margin status, type of re-operation performed and final histological diagnosis. Results: There were 178 wire-localized excisions. Second and third re-operations were performed in 44.8% and 5%, respectively. Mean volume excised was similar between the group with the conservative procedure only (97 g) and the group requiring re-operation (101 g). The tumor type or grade did not correlate with the need for additional surgery. Reexcised specimens revealed residual tumor in 40% of cases. For the palpable lesions, the re-excision rate was 30%. Conclusion: While our re-operation rates for hook-wire localized lesions is in keeping with what has been reported in

Abstracts / Pathology – Research and Practice 200 (2004) 631–655

the literature, we feel it is unacceptably high. There appears to be no relation to volume excised or histological tumor type, factors associated with second surgery in previous studies. Strategies to lower re-operation rates will be discussed.

52

Extranodal composite lymphoma (mantle cell and marginal zone lymphomas) in Sjogren’s syndrome

M.T.S. RAD, B. ROLAND, I. AUER, A. MANSOOR Department of Pathology and Laboratory Medicine, Division of Hematopathology, University of Calgary, Calgary, Alberta T2N 2T9. Introduction: Patients with Sjogren’s syndrome (SS) are at increased risk (44-fold of general population) of developing Non-Hodgkin lymphoma (NHL). Marginal zone B-cell lymphoma (MZL) is the most common type of lymphoma in these patients while some cases of diffuse large B-cell lymphomas have also been described. No case of primary Mantle cell lymphoma (MCL) arising in the background of SS has previously been reported. We report the first case of SSassociated composite NHL with concurrent Mantle cell lymphoma and Marginal zone B-cell lymphoma components. Case presentation: The patient is a 67-year-old male, who presented with bilateral parotid mass and associated symptoms of SS. H&E sections of the resected mass, demonstrated intense lymphoepithelial sialadenitis. Multiple foci of small neoplastic lymphoid cells with irregular nuclear contours consistent with Mantle cell lymphoma were identified. Other focal areas of lymphoid cells with monocytoid appearance showing morphology of marginal zone lymphoma were also present. The neoplastic cells of mantle cell area were positive for CD5, CD20, CD43, Cyclin D1and kappa light chain restriction by immunostaining. The neoplastic cells of marginal zone areas were positive for CD20 and lambda light chain restriction and negative for CD5, CD43 and Cyclin D1 immunostains. These two different clonal populations with dissimilar expression of CD5and light chain restriction were demonstrated by flow-cytometry as well. The FISH analysis for t (11;14) was positive. The bone marrow was not involved and the clinical stage of 1b was established. The patient is being treated with radiation therapy. Conclusion: Occurrence of an aggressive lymphoma concurrent with an indolent type not only affects the prognosis but also changes the clinical management in these patients.

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Correlation of immunophenotypic features of mediastinal large B cell lymphoma with clinical risk assessment

M.T.S. RAD1, D.A. STEWART2, Y. AUER1 University of Calgary 1 Department of Pathology and Laboratory Medicine 2 Division of Medical Oncology, Calgary, Alberta T2N 2T9 Introduction: Mediastinal large B cell lymphoma (MedDLBCL) is a subtype of Diffuse Large B cell Lymphoma (DLBCL) with unique clinical, molecular and immunophenotypic features. Prognostic significance of expression of bcl-2/

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bcl-6/CD10/Ki 67 has been reported in the context of DLBCL but not validated in the context of Med-DLBCL. Objectives: This study is designed to correlate the immunophenotypic features of Med-DLBCL with clinical risk assessment to plan the primary therapeutic modalities in these patients. Materials and methods: Forty-four patients with clinical criteria of ‘‘high-risk’’ NHL were found in TBCC Lymphoma database (1997–2003). These patients were previously subdivided into intermediate high-risk (HI) and aggressive highrisk (HA) groups. The morphologic features and comprehensive immunophenotypic expression of all 44 cases were reviewed. Twelve out of 44 cases met the criteria for MedDLBCL. Bcl-2, Bcl-6 and Ki67 were used in this group to study the prognostic correlation. Results: Review of the clinical data revealed that 6/12 were classified as HI and 4/12 as HA group. The clinical data were not available in 2/12 patients. In 7/12 cases the expression of bcl-2, bcl-6 and Ki67 was found. These three markers were negative in 2/12 cases, which were represented in HA group (2/4). The co-expression of bcl-2/bcl-6 was only found in HI group (4/6). Three of those 4 cases were also positive for Ki67. Conclusions: Med-DLBCL represented a high fraction (27%) of high-risk lymphoma patients in this study. This implies that Med-DLBCL follows an aggressive clinical course. Co-expression of bcl-2/bcl-6/Ki67 was seen only in HI group (3/6), while simultaneous absence of bcl-2/bcl-6 and Ki67 was only observed in HA (2/4). These data suggest that the pattern of bcl2/bcl6/ Ki67 may correlate with clinical behavior of Med-DLBCL and lead the primary therapeutic plan (conventional chemotherapy vs. frontline ABMT) on this subcategory of patients.

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Malignant pleural mixed type mesothelioma with osteogenic sarcoma and squamous differentiation

M.T.S. RAD1, S.C GRONDIN2, M.A. DUGGAN1 University of Calgary, 1 Department of Pathology and Laboratory Medicine 2 Department of Surgery, Calgary, Alberta, Canada T2N 2T9 Malignant mesothelioma arises from the mesothelial cell of the serosal cavities. Divergent differentiation by the cell towards an epithelial and mesenchymal phenotype results in a number of histological types. The three major histological types are epithelial (60–76%), sarcomatoid (2–16%) and mixed (22–24%). Unusual variants include deciduoid, well-differentiated papillary and clear cell types. Also rare sarcomatous differentiation including chondrosarcoma and osteogenic sarcoma can occur within the tumor. Herein we present a case of mixed malignant mesothelioma of the pleura that uniquely showed osteogenic sarcoma and squamous differentiation. The patient was a 47-year-old man, former smoker who presented with a 12-month history of shortness of breath and 10-lb weight loss. Chest X-ray and CT scan showed right side pleural effusion and a pleural mass, which on biopsy was an epithelial malignant mesothelioma. The patient was selected for surgical resection but because of tumor invasion into the chest wall, the procedure was discontinued. Histopathological examination of the surgical biopsies demonstrated a mixed malignant mesothelioma composed of carcinomatous and sarcomatous component. The carcinomatous component was

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formed of small tubular glands lined by columnar type malignant cells with focal transition to a pattern of squamouslined cysts filled with keratin. The sarcomatous areas were composed of solid sheets of plump spindle cells including a focus of small blue cells with malignant osteoid formation featuring an osteogenic sarcoma. The tumor stage was T3N0M0 and the patient has survived 4 months on a trial of Alimta and Cisplatin. The case adds to the multiplicity of histological differentiation that can occur in a malignant mesothelioma.

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Lympth node metastases in low-grade endometrial stromal sarcoma

J. RIOPEL1, M. PLANTE2, M-C. RENAUD2, M. ROY2, B. TEˆTU1 1

Departments of Pathology Gynecologic Oncology, Center Hospitalier Universitaire de Que´bec (CHUQ) - Hoˆtel-Dieu de Que´bec, Que´bec 2

Low-grade endometrial stromal sarcoma is a rare malignant tumor with an indolent behavior but frequent recurrences. It is usually treated with hysterectomy and bilateral salpingo-oophorectomy. Lymph node random biopsies or complete dissections are rarely performed, especially when the diagnosis is made after a hysterectomy for a presumed benign condition. This surgical approach is based on the idea that stromal sarcomas disseminate hematogenously and that lymph node metastases are rare. The objective of this study was to review our experience on lymphatic dissemination in patients with low-grade endometrial stromal sarcoma and to compare with data from the literature. Fifteen patients with either random lymph node biopsies or a complete lymph node dissection at some point in the course of their evolution were found from the files of l’Hoˆtel-Dieu de Que´bec (CHUQ). Five of these patients (33%) presented lymph node metastases. Literature review shows that very few studies focused on nodal spread in low-grade endometrial stromal sarcoma. Part of those studies have grouped different types of uterine sarcomas assuming that they would all behave similarly. Moreover, most studies focusing specifically on endometrial stromal sarcoma did not sample lymph nodes. Only four articles with data on lymph node sampling were retrieved. Of them, only one case of metastasis was found out of a total of ten patients. These findings suggest that the incidence of lymph node involvement in low-grade endometrial stromal sarcoma is higher than expected. More extensive sampling of lymph nodes in these patients may allow a better understanding of the prognostic significance of these metastases.

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Signet-ring cell change in clostridium difficile pseudomembranous colitis J. RIOPEL, F. NAUD Department of Pathology, Center Hospitalier Universitaire de Que´bec (CHUQ) - Hoˆpital St-Franc¸ois d’Assise, Que´bec Signet-ring cell change in pseudomembranous colitis was first described in 1996. Since then, a few case reports and one series were published on the subject for a total of 20 reported cases.

Some authors suggested that signet-ring cell change could be associated with more severe cases of pseudomembranous colitis. The only series published, measured an incidence of 28% (14/50) of signet-ring cell change in pseudomembranous colitis. Twelve of the 14 positive cases were biopsies. The objective of this study was to measure the incidence of signetring cell change in autopsy and colonic resection specimens of pseudomembranous colitis. We reviewed all cases of pseudomembranous colitis seen in CHUQ since 2001. Seven autopsy cases or intestinal resections were found and 5 of them presented signet-ring cell changes (71%). Changes were focal and were not mentioned in original pathology reports. Eight biopsies were also found and none of them presented signet-ring cells. These results suggest that signet-ring cell change might be a very frequent finding in autopsy and resection specimens of pseudomembranous colitis. The focal nature of the changes may explain the rarity of reported cases in the literature as well as the lower frequency seen in biopsy cases. C. difficile toxins have been shown to induce cell rounding in intestinal epithelial cells in numerous in vitro studies. A link between these experimental effects and signet-ring cell change is proposed.

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‘‘Sir, There’s a cell in my ink’’ or contamination of ink by cells in a surgical pathology laboratory

T. ROUSE, D.K. DRIMAN Department of Pathology, London Health Sciences Center, University of Western Ont., London, Ont., N6A 5A5 Background: Surgical inks are used in most surgical pathology laboratories to mark areas of importance such as resection margins on surgical specimens. Often, the same Q-tip or some other inking device, is reused repeatedly when inking a specimen, leading to the possibility of transferring cells from one specimen to another, and thereby creating artifactual microscopic findings. Aim: To investigate whether containers of ink used for inking multiple specimens harbor cells, and thereby create a risk for contamination of specimens. Methods: Thirteen ink containers (14 specimens total) were analyzed without the knowledge of staff performing gross examinations. The ink remaining in the container was diluted to a 1:7 ratio with formalin. The ink–formalin mixture was centrifuged and the resultant pellet embedded in paraffin and processed in the standard fashion. Slides were stained with hematoxylin and eosin. Results: All blocks demonstrated cellular debris, and 3 of 14 blocks (21%) demonstrated recognizable and intact cells and/ or tissue fragments. Conclusions: Cells and tissue were identified in containers of ink, implying that these could potentially be transferred from one surgical specimen to another. We recommend that at the time of specimen inking, a small aliquot of ink be transferred from the ink container to a single-use, disposable cup, which would act as the source of ink for a single specimen.

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Primary intravascular large B-cell lymphoma of the uterus—a diagnostic challenge

M. SUR1, C. ROSS1, F. MOENS2, D. DAYA1

Abstracts / Pathology – Research and Practice 200 (2004) 631–655 1

Department of Anatomical Pathology, Henderson Hospital Juravinski Cancer Center, McMaster University, Hamilton, Ont., L8V 5C1 2

Intravascular lymphoma is a rare subtype of extranodal diffuse large B-cell lymphoma characterized by the presence of lymphoma cells in the lumina of small vessels without obvious extravascular tumor mass or leukemia. To the best of our knowledge, this is the first case report of this entity in the uterus. A 63-year-old patient presented with postmenopausal bleeding which initiated an endometrial curettage and hysteroscopy. The curettage material was reported as ‘‘undifferentiated malignant tumor’’. An ultrasound of the abdomen showed a 2 cm lesion in the spleen. CAT scan of the chest, abdomen and pelvis were normal. There was no evidence of organomegaly or B symptoms. A full staging workup including full hematologic investigation, bone marrow aspirate and biopsies were normal. The patient underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy, pelvic lymph node dissection and omental biopsy. The hysterectomy specimen grossly had a small irregular nodule measuring 0:4  0:3 cm2 in the endometrial cavity, anteriorly, proximal to the lower uterine segment and another nodule, 0:3  0:2 cm2 in the posterior uterine segment. Both tubes and ovaries were grossly unremarkable. The uterus showed classical features of an intravascular B-cell lymphoma comprising large- to medium-sized cells located in the lumina of small blood vessels predominantly in the corpus but also extending to the cervix, left tube and ovary. The diagnosis was further confirmed by a panel of immunohistochemical stains showing positivity for LCA, CD20, CD79A, Bcl2 and Bcl6. Molecular analysis by PCR showed a monoclonal B-cell proliferation. Fibrin thrombi occluding small vessels as is classically described in such cases was also demonstrated. The pelvic lymph nodes and omentum were negative for malignancy. We describe the 1st possible case of a primary intravascular B-cell lymphoma of the uterus confirmed by morphology, immunohistochemistry and molecular studies. Early recognition and accurate diagnosis of this aggressive form of lymphoma is essential for effective treatment and improved survival. Combination chemotherapy with or without radiotherapy is often effective and long-term survival appears to be possible only with early recognition and diagnosis.

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Primary cardiac sarcoma: case report and literature

review C. TATLIDIL, A. RAZA. A. COVERT, A. OSTRY Division of Anatomical Pathology, Department of Pathology, Dalhousie University, OEII Health Sciences Center, Halifax, Nova Scotia, B3H 2Y9 Primary tumors of the heart are very rare and the majority are benign myxomas. Sarcomas are the most frequently observed primary malignant cardiac neoplasms. Angiosarcomas are the most common primary cardiac sarcoma (25–37%). We report a case of an otherwise healthy 49-year-old female presenting with progressively worsening dyspnea and right-sided chest pain. Imaging studies revealed a large left atrial mass that was initially believed to be a myxoma, and was subsequently

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resected. Morphological evaluation of the surgical specimen revealed a sarcoma with a variable appearance and high-grade malignant features. The malignant cells demonstrated only focal weak actin and diffuse strong vimentin positivity. The remainder of the immunohistochemical panel was negative. A diagnosis of an unclassified sarcoma was favored based on morphology and immunohistochemical profile, although a diagnosis of myxosarcoma was also entertained. Primary cardiac sarcomas are classified in a similar fashion to sarcomas in other sites, and all share a poor overall prognosis. Surgery remains the main treatment option, although it is rarely curative due to the difficulty in obtaining complete excision. The benefits of transplantation, adjuvant chemotherapy and/ or radiation therapy have yet to be proven according to published reports. As illustrated by this case, classification and diagnosis of primary cardiac sarcomas can be challenging. With relatively few published case series, the prognostic and treatment implications of correct classification remains undetermined and highlights the need for further study.

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Virus epstein-barr et cancer du sein dans le center tunisien

A. TRABELSI, M. MOKNI, E. MUTIJIMA, A. MOROU, A. SOUA, S. KORBI Laboratoire d’Anatomie et cytologie Pathologiques, CHU Farhat Hached Sousse, Tunisie Dans le but d’e´valuer la pre´valence de l’implication du virus d’Epstein-Barr (EBV) dans la gene`se du cancer mammaire, en particulier le carcinome me´dullaire et le CCI de haut grade au stroma lymphoı¨ de et de discuter une e´ventuelle implication pronostique de l’EBV pour ces deux types de cancer, nous avons proce´de´ a` une e´tude re´trospective de 36 cas de carcinome mammaire diagnostique´s au Laboratoire d’Anatomie et de Cytologie Pathologiques du C.H.U. Farhat Hached de Sousse entre 1987 et 2002. Dix huit cas de cancer me´dullaire et 18 cas de CCI de haut grade au stroma lymphoı¨ de ont e´te´ analyse´s. L’aˆge moyen de nos patientes est de 54,3 ans. La de´tection du virus a e´te´ effectue´e par la technique d’hybridation in-situ a` l’aide d’oligonucle´otide EBER et par immunohistochimie en utilisant les anticorps anti-Zebra et anti-LMP1. L’hybridation in-situ a montre´ la pre´sence de l’EBV au niveau des cellules tumorales dans 5 cas, soit 14%. Une positivite´ des cellules tumorales avec l’anticorps anti-LMP1 a e´te´ note´e dans 5 cas, soit 14%, de meˆme une positivite´ allant de quelques cellules a` 80% des cellules tumorales avec l’anticorps BZ1 antiZebra, a e´te´ note´e dans 39% des cas. L’e´tude des facteurs pronostiques a montre´ que l’EBER est positive dans 11% des cas de CCI de haut grade au stroma lymphoı¨ de et dans 16,5% des cas de carcinome me´dullaire, deux cas de cancer EBV positif sont associe´s a` un envahissement ganglionnaire supe´rieur a` 3 ade´nopathies, EBV est de´tecte´ plus fre´quemment dans les tumeurs qui n’expriment pas les re´cepteurs hormonaux, aucune association entre la pre´sence de l’EBV et les autres facteurs pronostiques tels que l’aˆge au moment du diagnostic, la taille de la tumeur et le statut me´nopausique. La signification pathoge´nique de l’EBV dans le cancer mammaire reste un sujet de controverse. Toutefois, l’EBV peut eˆtre conside´re´ comme e´tant un facteur pronostique ou meˆme une cible the´rapeutique. Le vaccin hhpDNA-base´ii repre´sente le dernier de´veloppement dans la strate´gie de vaccination contre

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ce virus, un tel progre´s me´rite d’eˆtre mieux e´tudie´ en pathologie humaine.

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Le carcinome sereux papillaire developpe dans un polype de l’endometre: comportement clinico-pathologique & la surexpression de la prote´ine p53

SYLVAIN TRAHAN1, BERNARD TEˆTU1, PAUL-E´MILE RAYMOND2 1

Services d’anatomopathologie de radio-oncologie

2

Center Hospitalier Universitaire de Que´bec (CHUQ), Pavillon l’Hoˆtel-Dieu de Que´bec Universite´ Laval, Que´bec, Que´bec, Canada Introduction: Le carcinome se´reux papillaire peut se de´velopper a` partir d’un polype be´nin de l’endome`tre. Ce carcinome est particulie`rement agressif et est associe´ a` un mauvais pronostic meˆme lorsque de´couvert a` un stade pre´coce. Une mutation du ge`ne suppresseur p53 pourrait eˆtre a` l’origine du de´veloppement rapide de cette ne´oplasie et de son sombre pronostic. Cette e´tude vise a` de´terminer le comportement du carcinome se´reux papillaire de´veloppe´ a` partir d’un polype be´nin de l’endome`tre et d’e´valuer l’expression de la prote´ine p53. Mate´riel et me´thode: Des cas de carcinomes se´reux papillaires de´veloppe´s a` partir de polypes be´nins de l’endome`tre ont e´te´ identifie´s entre 1982 a` 2003 a` l’Hoˆtel-Dieu de Que´bec. Tout le mate´riel clinico-pathologique a e´te´ revu. L’e´volution des patientes a e´te´ obtenu par la re´vision des dossiers ou en communiquant directement avec les me´decins traitants. Une analyse immunohistochimique a e´te´ effectue´e afin de rechercher la surexpression de la prote´ine p53. Re´sultats: Treize cas de carcinomes se´reux papillaires de´veloppe´s dans un polype de l’endome`tre ont e´te´ identifie´s. L’aˆge moyen des patientes est de 72 ans, toutes ont eu un traitement chirurgical et 54% ont rec¸u un traitement adjuvant. Apre`s un suivi moyen de 22 mois, 54% des patientes e´taient de´ce´de´es ou vivantes avec maladie. Dix cas ont e´te´ teste´s pour l’expression de la prote´ine p53. Dans la grande majorite´ (80%) des cas, l’on observe une surexpression. Conclusion: Le carcinome se´reux papillaire de´veloppe´ a` partir d’un polype de l’endome`tre demeure une ne´oplasie avec un pronostic de´favorable. La surexpression de la prote´ine p53 permet de conclure que la mutation du ge`ne se produit pre´cocement et peut expliquer la progression rapide de la maladie et son sombre pronostic.

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IBF is an excellent fixative in prostate biopsy pathology

K. TRPKOV1, N. ALI-RIDHA2, P. RENAULT1, A. YILMAZ1 1 Rockyview General Hospital, Calgary Laboratory Services and University of Calgary, Alberta 2 Oshawa General Hospital, Ontario

Background: Optimal fixation of prostate needle core biopsies is of utmost importance for the prostate biopsy practice. The preferred prostate biopsy fixative has been 10% neutralbuffered formalin (NBF). Other fixatives that enhance the

nuclear morphology, such as Bouin’s, have been reported to interfere with the immunohistochemistry and decrease the sensitivity of the staining for high molecular weight cytokeratin (HMWK). Design: Since 1993 we have used the commercially available IBF fixative (Surgipath), that contains isopropyl alcohol, methanol, barium chloride and low percent formalin, to routinely fix all prostate biopsies in our centralized Urological Pathology for the Calgary Health Region. All prostate biopsies are fixed in IBF for 18–24 h, then processed and sectioned routinely in three separate levels. During the last three years, using a 10 core sampling protocol with site-specific submission, we have processed more than 5000 prostate biopsies in IBF. Results: IBF-fixed prostate biopsies exhibit excellent cytomorphology on H&E with superior nuclear morphology and crisp nucleoli, which particularly helps in establishing a diagnosis of small foci of prostatic cancer (vs. atypical glands) and highgrade prostatic intraepithelial neo-plasia (PIN). Immunoreactivity for HMWK (34bE12 and cytokeratin 5/6) and AMACR in IBF fixed biopsies is well preserved. The rates of prostate carcinoma, atypia, and PIN in our practice (41%, 4% and 13%, respectively) are comparable to the reported rates in formalin-fixed biopsy series. Sectioning of IBF fixed biopsies does not require additional time or technical skill in comparison with similar NBF-fixed biopsies (eg. liver, lung). IBF has a comparable cost to NBF. Conclusion: IBF is an excellent and cost-effective prostate biopsy fixative that enhances cytomorphology and preserves the tissue immunoreactivity and can be used as an alternative to NBF in routine prostate biopsy practice.

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The cytologic features of hyalinizing trabecular adenoma of the thyroid gland on liquid-based preparations: report of two cases

M. VAZIRI, M. KHALIL Department of Pathology, Calgary Laboratory Services, University of Calgary, Calgary, Alberta, Canada Introduction: Hyalinizing trabecular adenoma (HTA) is a rare thyroid neoplasm that behaves in a benign fashion. It displays many of the diagnostic nuclear features of papillary thyroid carcinoma (PTC), which makes its diagnosis a challenging task in cytology. The cytologic features of HTA described in recent literature are based on conventional direct smear preparations (CP). To our knowledge, those features on liquid-based preparations have not yet been described. We report the cytologic features of HTA in two thyroid fine needle aspirates (FNA) processed by the Thinprep method. Material and method: In the first case, the FNA of a thyroid nodule was received in Cytolyte, from which two thin-layer slides were prepared and stained by the Papanicolau method. In the second case, the thyroid nodule was an incidental finding during parathyroidectomy and FNA was performed intra-operatively. In this case, the aspirate was processed both by liquid-based and direct smear methods. Results: The thin-layer slides of both tumors revealed hypercellular aspirates composed of epithelial cells, which were disposed as dispersed isolated cells and syncytial fragments. Ribbons, trabeculae and pseudo-papillae were also present, but no follicles, true papillae, or monolayered sheets

Abstracts / Pathology – Research and Practice 200 (2004) 631–655

were identified. The cells were oval or elongated and frequently displayed dendritic cytoplasmic extensions. They exhibited enlarged, grooved nuclei with fine chromatin and indistinct nucleoli. Occasional intranuclear pseudo-inclusions were detected. In one of the cases, the backgound showed fragments of stroma, some of which were acellular and hyalinized. Colloid and psammoma bodies were not present in either case. Conclusion: Hyalinizing trabecular adenoma shares nuclear morphologic similarities with papillary thyroid carcinoma. However, it has distinctive architectural and background features on liquid-based aspirates that should suggest the diagnosis, when encountered.

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Metastatic epithelioid gastrointestinal stromal tumor in peritoneal fluid; a diagnostic pitfall on liquid-based cytology: a case report

M. VAZIRI, M. KHALIL, A. YILMAZ, Department of Pathology, Calgary Laboratory Services, University of Calgary, Calgary, Alberta, Canada T2N 4M1 Introduction: Gastrointestinal stromal tumors (GISTs) are the most common mesanchymal tumors of the gastrointestinal tract. Approximately 20–30% of them behave in a malignant manner, with the peritoneum and liver being the most common sites for metastases. Because of the recent advent of specific treatment for metastatic GIST, it is important to recognize this tumor on cytology material or biopsies from the metastases. To our knowledge, there is only one case report on the cytomorphology of metastatic epithelioid GIST in ascitic fluid, describing its resemblance to metastatic adenocarcinoma on a Cytospin preparation. We report the cytologic features of another case, which was processed by the Thin-prep method. Case: A 79-year-old male presented with a gastric mass and ascities. Thin-layer slides prepared from the peritoneal fluid and stained by the Papanicolau method revealed a hypercellular material which included multiple clusters of malignant epitheliod cells. Many of these clusters displayed a peculiar whorled pattern and contained cells with vacuolated cytoplasm. Isolated malignant cells and mesothelial cells were present in the background. No cell block was available for immunocytochemistry and the cytomorphology was initially interpreted as a metastatic adenocarcinoma. Subsequently, a biopsy from a liver metastasis revealed an epitheliod GIST which was confirmed by immunohistochemistry for CD117 and CD34. The cytomorphology of the liver metastasis correlated with that of the malignant cells in the peritoneal fluid. Conclusion: Epithelioid GIST mimics metastatic adenocarcinoma in liquid-based cytology of the serous effusions and is a diagnostic pitfall, with therapeutic implications, that can be avoided by the routine use of immunocytochemistry.

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Co-presentation of aortic dissection and large bowel sarcoidosis in an unusual case of turner syndrome

M. VAZIRI, R.T. OGILIVE Department of Pathology, University of Calgary, Calgary, Alberta

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Introduction: Although gonadal dysgenesis and failure of pubertal development are main features described in Turner syndrome (TS), very rare cases of (45XO) TS have been reported to have spontaneous sexual development and ovulation. There is also a higher frequency of autoimmune disorders and inflammatory bowel disease in patients with TS. Cardiovascular malformations associated with this syndrome account for decreased life expectancy in young adults. We highlight the rare and unusual manifestations of TS. Design: Case report: We present a very unusual case of cytogenetically proven 45XO in a patient with history of menstruation and breast reduction. This short-statured, 26year-old female presented with recent onset of increasing retrosternal, epigastric and abdominal pain associated with low-grade fever and diarrhea. During initial hospital investigation she had a sudden cardiopulmonary arrest and died. Clinicians were not aware of her genetic condition until after her death. Results: Autopsy identified ruptured dissecting aneurysm of the ascending aorta that had occurred in the setting of a congenital bicuspid aortic valve. There was diffuse mucosal ulceration of the colon and microscopic examination revealed multiple transmural granulomata. Similar incidental granulomata were present both in the pulmonary parenchyma and hilar lymph nodes and sarcoidosis was a diagnosis of exclusion. Graafian follicles were identified in both ovaries. Conclusion: Spontaneous ovulation is very rare in TS and breast reduction has not previously been reported. Because of the wide somatic manifestations in TS, a high degree of suspicion is required to diagnose potentially lethal cardiovascular malformations, especially in short-statured, young females with chest symptoms. Co-presentation of acute colitis and aortic dissection is very rare and as demonstrated in this case, may make the clinical scenario even more complicated. To our knowledge, sarcoidosis with involvement of colon has not been reported in TS and is difficult to differentiate from Crohn’s disease.

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Use of histology and magnetic resonance imaging for the identification of bone metastases

MICHAEL H. WEBER1, JONATHAN C. SHARP2, THOMAS H. HASSARD3, F. WILLIAM ORR4 1

Department of Pathology, University of Manitoba 3 Department of Community Health Science, University of Manitoba 4 Institute for Biodiagnostics, National Research Council of Canada 2

Background: Bone is a frequent site of cancer metastases. Current imaging modalities can only identify these lesions at a late stage when curative treatment is difficult or impossible. Design: Intracardiac injection of 10  106 B16F1 melanoma cells was used to induce bone metastases. The femurs of C57Bln6 mice both with and without tumor were examined in vivo using a multi transverse sliced 2D gradient echo (GE) and spin echo (SE) pulse sequence on an 11.7 T MRI scanner. The bones were then examined by histomorphometry. A thresholding analysis technique was applied to histology and MRI,

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to generate contour lines, delineating the boundaries between bone, marrow and metastatic tumor. Results: In non-tumor-bearing mice, optimal correlation of MRI results with histological ‘‘gold standards’’ was obtained using a short echo time GE versus a long echo time SE sequence ðpp0:01Þ. GE images were acquired with a maximum in-plane resolution of 35 mm. Our results demonstrated that the percent area of marrow increases and percent area of trabecular bone and cortical bone thickness decreases moving from the epiphyseal growth plate to the diaphysis ðpp0:001Þ. In contrast, metastatic melanoma replaced the marrow space and no significant change in trabecular bone or marrow percentage was noted ðpp0:001Þ. Conclusion: Our quantitative evaluation using MRI in vivo was found to be an effective means, to visualize with high resolution both the normal variation in bone microanatomy and effects of metastatic melanoma.

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Diffuse large B-cell lymphoma presenting with hyponatremia secondary to bilateral adrenal involvement: an autopsy case report

M.J. WOOD1, K.R. CRAWFORD2, D.A. MALATJALIAN1 1

Department of Pathology, Queen Elizabeth II Health Sciences Center, Halifax, Nova Scotia 2 Department of Medicine, Queen’s General Hospital, Liverpool, Nova Scotia Reported here is the unusual case of a 66-year-old man who presented with symptoms of hyponatremia and a serum sodium of 125 mmol/l. Computed tomography scan showed abdominal lymphadenopathy and biopsy confirmed diffuse large B cell lymphoma. The literature shows involvement of the adrenals by lymphoma to be less common than solid tumor metastases, and suggests clinical hypoadrenalism occurs when 90% of the adrenal tissue is compromised. Autopsy of this patient confirmed stage IV lymphoma involving approximately 50% of adrenal tissue. No other metabolic or anatomical abnormalities were found to explain the hyponatremia, therefore, primary hypoaldosteronism is the proposed mechanism for the hyponatremia. This case is an example of the uncommon presentation of lymphoma as hyponatremia and highlights the importance of sampling the adrenals and estimating the extent of involvement by malignancy for clinicopathological correlation.

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The cytological analysis of host cellular response to intraperitoneally transplanted microcapsules containing islet xenografts H. YANG, B.Y. XU, R. MACINTOSH, J.R. WRIGHT Jr. Department of Pathology, QEII HSC, Dalhousie University, Halifax, Nova Scotia Introduction: We have previously reported that microencapsulation can significantly prolong intraperitoneally (IP) transplanted fish islet xenograft survival in murine models. However, graft long-term survival was limited in NOD

recipient, a mouse model for human type I diabetes. Strong cellular reaction around the encapsulated islets is observed histologically. This study is to quantify host cellular reaction in this transplant model. Methods: Tilapia fish islets were harvested, encapsulated and transplanted IP into diabetic NOD mouse recipients as previously described. Two weeks post transplant, peritoneal lavage was performed. Absolute cell number was counted using flow cytometry. Cytospin slides were prepared and stained with Gemsa and Papanicolaous stains. Differential cell numbers were analyzed. The islet grafts were later removed from the recipients for histological study. Recipients that received no transplant or empty capsules were used as controls. Results: The absolute cell number in the peritoneal lavage sample are 10 times higher in recipients receiving microcapsules containing islets than those which received empty capsules or no transplants. In particular, the mononuclear cells and eosinophils are dramatically increased in the former group over the control groups. Marked pericapsular cellular aggregations were seen histologically in the former group while the control groups show little or no such reaction. Conclusion: Microencapsulated islet xenograft induced heavy cellular response in NOD recipients after IP transplant. Mononuclear cells and eosinophils are particularly increased. This result may help to understand the mechanism of rapid rejection of microencapsulated islet xenografts by NOD mouse recipient.

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Micropapillary urothelial carcinoma: a study of eight patients

A. YILMAZ, A. KULAGA, K. TRPKOV Anatomical Pathology, Rockyview General Hospital, and University of Calgary, Calgary, Alberta, T2V 1P9 Introduction and objective: Micropapillary carcinoma (MPC) is a rare variant of high-grade urothelial carcinoma with an aggressive clinical behaviour. MPC of the urinary bladder shows striking resemblance to MPCs originating from other organs, such as breast, ovary and lung. Methods: We studied 8 patients with MPC of the urinary bladder, diagnosed in our institution during a three-year period. A total of 17 specimens were reviewed from these patients, including 13 bladder biopsies, 2 cystectomies and 2 distant metastatic sites. Immunohistochemical stains were performed to determine the profile of MPC of the bladder. Results: All patients had invasive urothelial carcinoma showing a predominant micropapillary pattern, which was accompanied by a minor component of conventional urothelial carcinoma. Extensive muscularis propria involvement was demonstrated in 4/5 specimens where muscularis propria was present in the specimen. Two patients who had follow-up cystectomies demonstrated a high-stage (pT3) disease. Micropapillary morphology was also preserved in the metastatic sites, including one regional lymph node and two nonlymphoid distant metastases. CK7 and CK19 were strongly positive in all patients and CK20 was positive in 7/8 patients. CEA(m) was positive in 6/8 and p53 was positive in 5/8 patients. ER/PR and TTF1 were negative in all cases. Conclusions: MPC of the urinary bladder is a distinct morphologic variant of urothelial carcinoma with high

Abstracts / Pathology – Research and Practice 200 (2004) 631–655

propensity for bladder wall invasion and metastatic spread. Immunohistochemistry may be useful in the differential diagnostic work-up of a carcinoma with micropapillary features, as MPC of different organs exhibit almost identical histologic appearances. Positive immunostaining for CK7, CK19 and CK20, and negative staining for TTF1 and ER/PR in an MPC strongly suggests a urinary bladder primary.

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Kallikreins are potential new breast cancer biomarkers

KLK10 showed no expression in 8 tumors, lower than normal in 5 and compared to normal in one tumor. Our results indicate that kallikreins are potential diagnostic/prognostic biomarkers of breast cancer.

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The human Kallikrein protein 5 (hK5) is enzymatically active, glycosylated and forms complexes with two protease inhibitors

G.M. YOUSEF1,2, M. POLYMERIS2, N. WHITE1, J-D. ROBB1, G.M. YACOUB3, AHMED A RAOUF, E.P. DIAMANDIS2

G.M. YOUSEF1,2, M. POLYMERIS2, SHIRLEY HUTCHINSON, J-D. ROBB1, A. SOOSAIPILLAI2, EMAN SERRY, E.P. DIAMANDIS2

Departments of Pathology 1 Memorial University, St. John’s, Newfoundland 2 Mount Sinai Hospital, Toronto, Ontario 3 University of Virginia Roanoke, VA

Departments of Pathology 1 Memorial University, St. John’s, Newfoundland 2 Mount Sinai Hospital, Toronto, Ontario

Recent evidence suggests that many kallikrein genes are differentially regulated in different malignancies. In this study, we utilized the Serial Analysis of Gene Expression (SAGE) and Expressed Sequence Tag (EST) databases of the Cancer Genome Anatomy Project to perform in-silico analyses of the expression of the 15 human kallikreins in normal and cancerous breast tissues using different analytical tools including Virtual Northern blotting (VNB), Digital Differential Display (DDD) and X-profiler analysis. We also experimentally verified our findings. Our results indicate that 5 kallikreins (KLK5, 6, 8, 10) are down-regulated in breast cancer. Analyzing 8 normal and 24 breast cancer SAGE libraries indicated moderate to high kallikrein expression densities in normal breast (27–319 tags per million; tpm, in 2–5 out of 8 libraries), compared to no or low expression (0–34 tpm in 0–2 libraries out of 24) in cancerous tissues. Screening the EST databases also showed that all mRNA clones isolated for these genes, except for one, were from normal breast, with no clones detected from breast cancer (with the exception of KLK8). X-profiler comparison of two pools of normal and breast cancer libraries further verified this significant down-regulation. We experimentally verified our findings by RT-PCR analysis. While KLK5 was expressed at high levels in all normal breast tissues, it was only detectable in 3 out of 14 cancerous breast tissues examined. KLK6 was strongly positive in normal breast tissue, but was not expressed in 9 out of 14 tumor tissues, lower than normal in 3. KLK8 also showed strong bands in normal tissues, compared to undetectable expression in 5 tumor tissues, lower than normal in 7 tumors.

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Kallikreins are a group of 15 serine proteases. Binding of kallikreins to protease inhibitors is an important mechanism for regulating their activity and, as is the case with PSA (hK3) has potential clinical applications. Human kallikrein protein 5 (hK5) is newly discovered kallikrein that was shown to be differentially expressed in different malignancies. Incomplete recovery of hK5 was observed in serum, suggesting its binding to inhibitors. In this study, recombinant hK5 protein was produced in yeast and mammalian systems. HPLC fractionation, followed by hK5-specific and hybrid assays, immunoblotting, and radiolabeling experiments were performed to study the interactions of hK5 and proteinase inhibitors. Deglycosylation analysis was also done and enzymatic activity of hK5 was tested using different synthetic trypsin and chymotrypsin fluorogenic substrates. Our results show that in addition to the free form, hK5 forms complexes with a1 antitrypsin and a2 -macroglobulin in serum and ascites fluid. These complexes were detected by hybrid assays using antihK5 monoclonal antibody for capture and different inhibitor antibodies for detection. The ability of hK5 to bind to these inhibitors was also verified in-vitro. Serum samples spiked with I125 -labeled hK5 showed the distribution of the protein in two higher molecular mass (bound) forms, in addition to the unbound form. In addition, mixing a2 -macroglobulin with hK5 in a BSA medium resulted in a significant decrease in detectable hK5. The hK5 mature enzyme is enzymatically active and shows trypsin-, but not chymotrypsin-like, activity. Glycosylation/Deglycosylation analysis showed that hK5 has a higher than predicted molecular mass due to glycosylation, which returns to normal after deglycosylation.