Cardiac valve repair: novel techniques

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PATHOLOGY UPDATE 2009 ABSTRACT PUBLICATION

mutations of PTEN, tumour cells can protect themselves against apoptosis by the way of lipid signal transduction. Methods: In this study, the relationship of PTEN and survivin expression with apoptosis was investigated by the means of immunohistochemical method in 39 patients with invasive breast cancer (IBC) and ductal carcinoma in situ (DCIS) within the same breast tissue. Results: A decrease or loss in PTEN expression was observed in an important portion in DCIS (46.7%) and IBC (71.8%). In cases with invasive ductal carcinomas, strong staining with survivin was observed in 33.3% of cases, while there was weak staining in 61.6% and no staining in 5.1% of cases. All of the DCIS tumour cells were positive with survivin but staining was weak. Apoptotic index was higher in IBC than in DCIS, but there was no significant difference. No relationship was found between apoptosis and PTEN or survivin expression in breast carcinoma. Conclusion: Our results suggest that a decrease in PTEN expression and increase in apoptosis is important in progression of IBC.

CHARACTERISATION OF FACTOR VII DEFICIENCY DUE TO A HOMOZYGOUS MISSENSE MUTATION (L-48P) IN THE SIGNAL SEQUENCE K Shinozawa1, T Suzuki2, K Amano1,2, I Seita2, M Otaki2, S Fujita2, H Inaba2, K Fukutake1,2 1 Department of Molecular Genetics of Coagulation Disorders, Tokyo Medical University; 2 Department of Laboratory Medicine, Tokyo Medical University, Tokyo, Japan We investigated the molecular basis of coagulation factor VII (FVII) gene in a Japanese patient with FVII deficiency. FVII activity (FVII:C) and antigen (FVII:Ag) were 11.5% and 12.7%, respectively. Sequence analysis revealed a homozygote for a T to C transition at nt.38 in exon 1a, resulting in -48Leu(ctt)?Pro(cct), which is located in the hydrophobic core of the signal peptide. Four mutations (L-48P, L-48V, L-48R, and L-48 amino acid del.[L-48 a.a. del.]) were independently introduced in the pcDNA3.1/FVII plasmid by the site-directed mutagenesis, and the proteins were expressed in HEK-293 cells. FVII:Ag of L-48 a.a.del. mutant was detected as 57% ,and the remaining mutants were detected as more than 95% of wild-type in the conditioned media, respectively. FVII:C of L-48 a.a.del. and L-48V mutants were detected as 82% and 87% ,and L-48P and L-48R mutants were detected as 100% of wild-type in the conditioned media, respectively. In the expression experiments using HEK-293 cells, these results raise the possibility that Leu-48 deletion caused effect on intercellular degradation, and these results suggest that the substitution with only one Leu-48 had little effect on the secretion. In conclusion, these results support a role for the Leu-48 in the signal peptide of FVII.

METASTATIC MALIGNANT PILOMATRIXOMA: A CASE REPORT AND REVIEW OF THE LITERATURE R Bhuta, G Wright, Q Lau, S Bhuta Pathology Queensland, Gold Coast Hospital; Department of Medical Imaging, Gold Coast Hospital, Queensland, Australia Pilomatrixoma is a common benign adnexal tumour with differentiation towards matrix of the hair follicle. It is typically located in the head and neck region. The tumour is well circumscribed, lobular, cystic and composed of three major cell types: proliferating

basaloid cells, eosinophilic squamous cells and shadow cells which represent dead cells. We report a rare case of malignant pilomatrixoma of the posterior occipital region in a 43-year-old female with metastases to C2 vertebra. The case was originally reported as proliferating pilomatrixoma. Bones of the head and neck region are a common site for metastases in malignant pilomatrixoma. Malignant pilomatrixoma is extremely rare. There are 90 cases regarded as acceptable reported in the English literature and ninety cases of metastasis. Because of its rarity, the precise incidence and prevalence of malignant pilomatrixoma are unknown. The diagnosis of malignancy is based on histological criteria which are not well defined and somewhat subjective. This includes cytological atypia, high mitotic activity with atypical mitosis, areas of confluent tumour necrosis, infiltrative growth pattern and vascular, lymphatic or perineural invasion. Reference: Manivel C, Wick MR, Mukai K. Pilomatrix carcinoma: an immunohistochemical comparison with benign pilomatrixoma and other benign cutaneous lesions of pilar origin. J Cutan Pathol 1986; 13: 22
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ONCOCYTIC ADRENOCORTICAL NEOPLASM: A RARE TUMOUR OF UNCERTAIN MALIGNANT POTENTIAL: A CASE REPORT Rakhi Bhuta1, Alfred Lam1,2, Queenie Lau1 1 Pathology Queensland, Gold Coast Hospital, Gold Coast; 2 School of Medicine, Griffith University, Gold Coast, Queensland, Australia Aims: Oncocytic adrenocortical neoplasms are uncommon. To date, less than 50 cases have been described in the English literature. They are mostly benign tumours but a couple of malignant cases have been reported. In this study, we reported an oncocytic adrenocortical neoplasm with some unusual features. Methods: A non-functional adrenal tumour was detected in a 39year-old woman incidentally on ultrasound for gynaecological symptoms. She underwent left adrenalectomy which showed a large mass weighing 1384 g and measuring 180 140115 mm. Histopathological examination of the mass was performed. Results: The tumour was composed of tumour cells with prominent oncocytic cytoplasm. Electron microscopy showed numerous mitochondria which confirmed the oncocytic nature of this tumour. The tumour cells showed weak staining for inhibin and a low Ki-67 (B5%). It fulfils one of the minor modified Weiss criteria for malignancy (i.e., large size and weight) but lacks other features of malignancy. Thus, it was diagnosed as oncocytic adrenocortical neoplasm of uncertain malignant potential. Conclusion: We reported an unusual oncocytic adrenal neoplasm of uncertain malignant potential. To our knowledge, this entity is rare and follow-up is necessary to determine the biological behaviour.

CARDIAC VALVE REPAIR: NOVEL TECHNIQUES Jagdish Butany1,2, Adriana Luk3, Eric Ahn1, James I Fann4, Fred St. Goar5, Jan Komtebedde6 1 Department of Pathology, Toronto General Hospital/University Health Network, Toronto; 2 Department of Laboratory Medicine and Pathobiology, Faculty of Medicine University of Toronto; 3 Department of Medicine, University of Toronto, Toronto, Ontario, Canada

PATHOLOGY UPDATE 2009 ABSTRACT PUBLICATION

4 Department of Cardiothoracic Surgery, Stanford University, Stanford, CA; 5 El Camino Hospital, Mountain View, CA; 6 Evalve Inc., Redwood City, CA, USA Aims: Heart valve repair today includes several preclinical and clinical trans-catheter techniques, including the Evalve MitraClip, for mitral valve (MV) regurgitation by approximating the leaflets, creating a double orifice valve. This is undergoing clinical evaluation in the United States and is commercially available in Europe. We report the pathological findings of explanted MitraClip devices following chronic implantation in the porcine model. Methods: Twenty-one explanted porcine valves with MitraClip devices (implanted for 4, 12, 17, 24 and 52 weeks) were examined with light (16) and electron microscopy (5). All were examined, and submitted for routine histology and methyl methacrylate embedding. Haematoxylin and eosin, Gram and connective tissue stains were used. Results: Tissue in-growth and endothelialisation, proportional to duration of implantation, were found on the flow (atrial) and nonflow (ventricular) surfaces of the device. This tissue ‘encapsulated’ the device and bridged the gap between the mitral leaflets. Adjacent chordae tendinae were progressively incorporated into the fibrous tissue on the device, as early as 4 weeks, and in 100% of clips by 52 weeks. Conclusions: (1) The MitraClip device provides functional tissue apposition; (2) host tissue encases the device, but the valve continues to function well; (3) no device thrombosis was seen.

GIANT CELL AORTITIS: A DIFFICULT DIAGNOSIS. ASSESSING RISK FOR THE DEVELOPMENT OF ANEURYSMS AND DISSECTIONS Andrew Lee1, Adriana Luk2, Katie R Phillips1, Ki Dong Lim3, Tirone E David4, Jagdish Butany5

1 Department of Pathology, Toronto General Hospital/University Health Network; 2 Department of Medicine, Toronto General Hospital/University Health Network; 3 Department of Cardiology, Department of Medicine, University of Toronto; 4 Department of Surgery, Division of Cardiac Surgery, Toronto General Hospital/University Health Network; 5 Department of Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada Aims: Giant cell (GC) arteritis, a systemic vasculitis, commonly affects temporal arteries leading to severe headaches and vision loss. Involvement of the ascending aorta leads to aneurysms, ruptures and dissections. GC aortitis rarely has lesion specific symptoms and diagnosis is invariably made by histopathology. Methods: Four cases of histologically diagnosed GC aortitis of ascending aortic explants (aneurysm resections January 2007
April 2008) were assessed for clinical presentation leading to surgery. Specimens were photographed and sections examined using H&E, Movat pentachrome and immunohistochemistry (CD31, 45 and 68). Results: Hypertension and aortic incompetence (four patients), dyspnoea and chest pain/discomfort were noted in three patients. Histology showed medial fibrosis and marked destruction, infiltrates of macrophages and multinucleate GCs around residual elastic plates and lymphocytic infiltrates in intima and adventitia. Discussion: GC aortitis has non-specific symptoms and is difficult to diagnose clinically, with common symptoms being hypertension, aortic incompetence and dyspnoea/chest pain (3/4 patients) with

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investigations showing ascending aortic aneurysms and aortic valvular incompetence. Histological examination of excised tissues showed extensive medial destruction, and significant infiltrates of inflammatory cells and giant cells around elastic tissues. The role of follow-up, erythrocyte sedimentation rate (ESR) studies and immunosuppressant therapy needs consideration and evaluation.

CORE BIOPSY AND FINE-NEEDLE ASPIRATE CYTOLOGY DIAGNOSIS OF PLEXIFORM FIBROHISTIOCYTIC TUMOUR A CASE REPORT




Shaun Chou, Anita Achan Tissue Pathology, ICPMR, Westmead Hospital, Westmead, New South Wales, Australia Plexiform fibrohistiocytic tumour is a rare soft tissue tumour that occurs in children and adolescents. It commonly presents as a small, slow growing subcutaneous nodule in the distal extremities with a predilection for females. Histologically, it is characterised by three patterns: fibrohistiocytic, fibroblastic and mixed. The fineneedle aspirate (FNA) cytology of this entity is not well described. It behaves as a low grade malignancy, with a recurrence rate of 12.5
37.5%. Metastasis has occurred in up to 19% of cases (3/61 cases in one series), although this is considered to be rare. The list of differential diagnoses is wide, including benign fibrous histiocytoma, giant cell tumour of tendon sheath, fibromatosis, plexiform neurofibroma and myofibroma. A combination of awareness of the condition, appropriate histological features as well as other helpful features like age and location of the tumour should lead to the correct diagnosis. We present a case of a 19-year-old male with three recurrent forearm nodules who was diagnosed with plexiform fibrohistiocytic tumour after undergoing diagnostic FNA and core biopsy of the lesions.

PRIMARY SMALL CELL CARCINOMA OF THE PROSTATE (OAT CELL TYPE) A CASE REPORT




Rajendra Choubey, Puneet Tandon Department of Pathology, MGM Medical College, Indore, India Primary small cell carcinoma of the prostate is a rare anaplastic tumour with poor prognosis. The tumour may be pure small cell carcinoma as seen in lungs or may have a mixed pattern of adenocarcinoma with small cell carcinoma. A 69-year-old male patient presented with dysuria and increased frequency of micturition of 1 year duration. Investigations revealed mild anaemia and prostate specific antigen (PSA) of 20.1 ng/mL. Transurethal resection (TUR) of the prostate was done and the tissue was subjected to histopathological evaluation. A diagnosis of small cell carcinoma of prostate was given. There was diffuse homogenous proliferation of small carcinomatous cells which had replaced the normal architecture of the gland. The tumour cells were composed of uniform small cells having a pyknotic round nucleus. The chromatin was evenly distributed. Nucleoli were inconspicuous with scanty cytoplasm. Some of the tumour cells revealed intense granularity of cytoplasm. They were infiltrating the adjacent parenchyma. On immunohistochemistry, the tumour cells stained positive for neuron specific enolase (NSE) and negative for PSA and prostatic acid phosphatase (PAP).The patient died within 6 months because of metastases. Small cell (oat cell) carcinoma of the prostate is a rare aggressive tumour of the prostate with poor prognosis. It has a median