- Email: [email protected]
Glioblastoma with primitive neuroectodermal tumour-like components
270
CORRESPONDENCE
3. Regauer S, Nogales EF. Vulvar trichogenic tumors: a comparative study with vulvar basal cell carcinoma. Am J Surg Pathol 2005; 29: 479–84. 4. Braun-Falco M, Friedrichson E, Ring J. Subepidermal cleft formation as a diagnostic marker for cutaneous malignant melanoma. Hum Pathol 2005; 36: 412–5. 5. McNutt NS. Ultrastructural comparison of the interface between epithelium and stroma in basal cell carcinoma and control human skin. Lab Invest 1976; 35: 132–42. 6. Stanley JR, Beckwith JB, Fuller RP, Katz SI. A specific antigenic defect of the basement membrane is found in basal cell carcinoma but not in other epidermal tumors. Cancer 1982; 50: 1486–90. 7. Brenn T, McKee PH. Tumors of the hair follicle. Lazar AJF, McKee PH. Tumors and related lesions of the sebaceous glands. In: McKee PH, Calonje E, Granter SR. Pathology of the Skin. 3rd ed. Philadelphia: Mosby, 2005; 1260–1, 1313–4, 1543, 1559, 1586. 8. Carson FL, Lott RL. Microtomy. Carson FL. Fixation and processing. In: Brown RW. Histologic Preparation. Common Problems and Their Solutions. Illinois: CAP Press, 2009; 1–11, 15–25. 9. Ball NJ, Tanhuanco-Kho G. Merkel cell carcinoma frequently shows histologic features of basal cell carcinoma: a study of 30 cases. J Cutan Pathol 2007; 34: 612–9.
DOI: 10.1097/PAT.0b013e32835140d4
Glioblastoma with primitive neuroectodermal tumour-like components Sir, Central nervous system (CNS) tumours featuring areas of both high grade glioma and primitive neuroectodermal elements are rare and difficult to classify.1 They pose diagnostic and therapeutic challenges due to the presence of two components, each with distinct clinicopathological features, management principles, and prognoses.1 An additional problem is that these entities have been previously addressed in literature using variable terminology.2,3 A recent study of 53 patients, the largest to date, sought to clarify the nomenclature and biology of these neoplasms, and suggested a designation of ‘malignant glioma with primitive neuroectodermal tumour-like components (MG-PNET)’.1 We report a case of glioblastoma with PNET-like components (GBM-PNET), to our knowledge the first report of this entity in Australia. A 68-year-old male presented with a 6-week history of headaches and slurred speech. Magnetic resonance imaging
Pathology (2012), 44(3), April
(MRI) showed a large, partly cystic, peripherally enhancing mass centred in the right temporal lobe (Fig. 1A). The lesion caused superior displacement of the Sylvian fissure as well as compression of the midbrain by the uncus. The appearance was suggestive of a primary high grade neoplasm. A stereotactic right temporal craniotomy was performed with gross total resection of the lesion. Multiple fragments of grey-white tissue aggregating to 55 20 10 mm were received for histopathological examination. The entire macroscopic specimen was embedded for histopathological examination and revealed a large astrocytic neoplasm admixed with relatively circumscribed nodules of ‘small round blue cell tumour’ (Fig. 1B). The astrocytic component showed variable morphology, with regions of WHO grade II and III astrocytoma present, in addition to large areas of frank WHO grade IV glioblastoma (Fig. 2A–C). The astrocytic component was variably composed of pleomorphic fibrillary glial cells, as well as regions of gemistocytes with perivascular lymphocytic inflammation. Microvascular proliferation, mitotic activity, as well as geographic and pseudo-palisading necrosis were present. The nodules of ‘small round blue cell tumour’ consisted of cells with scanty cytoplasm and hyperchromatic ovoid to elongate nuclei with coarsely granular chromatin. Nuclear moulding, brisk mitotic activity, and karyorrhectic debris were present. Scattered anaplastic large cells with vesicular nuclei, prominent nucleoli, and multinucleated forms were also present (Fig. 2D–F). These relatively well circumscribed nodules resembled CNS PNET. Homer-Wright rosettes were not identified. Ancillary investigations included immunohistochemistry and in situ hybridisation (Fig. 3). The astrocytic component was diffusely and strongly immunoreactive for GFAP (Fig. 3A). EGFR immunoreactivity, though variable, was strong in the majority of the astrocytic component, including its infiltrating edge. p53 immunoreactivity was present in 50–60% of nuclei, and the proliferative index was up to 10% in the glioblastoma elements with Ki-67 labelling. The astrocytic component was not immunoreactive for synaptophysin, NSE, Neu-N, neurofilament or chromogranin, and showed moderate cell membrane immunoreactivity for CD56. In contrast, the PNET-like component showed diffuse strong cytoplasmic immunoreactivity for synaptophysin (Fig. 3B), CD56, and NSE, as well as weak patchy immunoreactivity
Fig. 1 (A) Peripherally enhancing, partly cystic mass centred in the right temporal lobe with a complex and irregularly enhancing soft tissue component on coronal T2 FLAIR MRI. Associated elevation of the Sylvian fissure, medial displacement of temporal lobe structures, and impingement on the brainstem by the uncus is seen. (B) GBM admixed with relatively circumscribed nodules of ’small round blue cell tumour’ (H&E).
Copyright © Royal College of pathologists of Australasia. Unauthorized reproduction of this article is prohibited.
CORRESPONDENCE
271
Fig. 2 (A) GBM with microvascular proliferation, and necrosis with peripheral pseudopalisading of nuclei (H&E). (B) Areas with gemistocytic differentiation (H&E). (C) Accompanying areas of hypercellularity with architectural and cytological atypia seen in low grade (WHO 2007 grade II) diffuse astrocytoma (H&E). (D) Admixed areas of PNET with prominent peritheliomatous growth pattern (H&E). (E) Elongate to ovoid, hyperchromatic nuclei of PNET with brisk mitotic activity (H&E). (F) Anaplastic large cells, with multinucleate forms in PNET-like components (H&E).
Fig. 3 (A) Strong, diffuse immunoreactivity for GFAP in the glioblastoma. (B) Strong, diffuse immunoreactivity for synaptophysin in PNET-like elements with nonimmunoreactivity in the adjacent GBM. (C) Focal EGFR gene amplification in GBM (inset: relative lack of EGFR amplification in PNET component) (CISH). (D) Representative FISH results; centromere 8 in green and MYCC in red. There are several copies of both red and green signals in most cells, indicating polysomy for chromosome 8 without specific MYCC amplification (FISH).
Copyright © Royal College of pathologists of Australasia. Unauthorized reproduction of this article is prohibited.
272
Pathology (2012), 44(3), April
CORRESPONDENCE
for Neu-N. Chromogranin and neurofilament were negative. The PNET-like elements lacked immunoreactivity for GFAP, which was restricted to rare single cells resembling entrapped glial cells. The proliferative index was 20–30% in these PNETlike areas with Ki-67 labelling, while p53 expression was seen in approximately 60–65% of nuclei. Immunoreactivity for EGFR was weak to absent in PNET-like areas. Both astrocytic and PNET components were non-immunoreactive for IDH1 (R132H). Fluorescent in situ hybridisation for MYCN and MYCC showed polysomy of chromosome 2 and chromosome 8, respectively, without amplification and with higher levels of polysomy seen in the PNET-like component. Chromogenic in situ hybridisation (CISH) for EGFR revealed an unusual pattern: there was high-level amplification of EGFR (>20 copies/cell) in a relatively circumscribed region of the glioblastoma component of the tumour (Fig. 3C), whilst other astrocytic areas contained only scattered (approximately 1–2%) individual cells with high level EGFR amplification. Rare single cells in the PNET component (<1%) also demonstrated high level EGFR amplification. Following surgical resection, the patient showed significant improvement, including resolution of headache and slurred speech. Spinal MRI showed no evidence of tumour dissemination. He is currently being managed with chemoradiotherapy as per the Stupp protocol.2 Platinum-based chemotherapy for CNS PNET has been reserved for recurrence or failure. The vast majority (>90%) of GBMs arise de novo without an underlying precursor lesion (primary glioblastomas), while the remainder have a history or histological evidence of a pre-existing low grade glioma (secondary glioblastoma). The GBM component in this case showed histological evidence of a secondary glioblastoma. Similar findings have been reported by Perry et al. and Shibahara et al. in their cases of MG-PNET.1,3 Perry et al. note that 89% of cases showed foci of diffuse astrocytoma on histology, with a significant subset also having a history of prior low grade glioma.1 They report a wide spectrum of lower grade glial elements, including fibrillary astrocytoma, gemistocytic differentiation, oligoastrocytoma, and oligodendroglioma, among others.1 Recently mutations in isocitrate dehydrogenase (IDH)-1 and -2 have been identified in 70–80% of low grade gliomas and secondary glioblastomas, and a sensitive and specific antibody to the most common mutant protein is now available.4,5 Interestingly, this tumour was negative for IDH1 (R132H). IDH1 mutations have been noted in a small proportion of supratentorial PNETs; however, the presence of IDH1 mutation in GBM-PNETs has not been investigated to date.6,7 The possibility that the emergence of PNET-like elements may preferentially occur in those secondary glioblastomas with wild-type IDH genes, or variant IDH mutations, remains to be examined. The histological features of the non-glial elements in this case were consistent with CNS PNET. The immunoreactivity for synaptophysin, NSE, and Neu-N confirmed their neuroectodermal lineage. The discrete nodular nature of the PNET-like elements was highlighted by immunoreactivity for synaptophysin (Fig. 3B) and NSE, and absence of GFAP immunoreactivity. Neu-N also showed patchy expression in these areas but not in the glioma components. Perry et al. demonstrated immunoreactivity for chromogranin in 29%, for Neu-N in 24% and for neurofilament in only 11% of their cases; thus a large majority of these tumours may lack chromogranin, and neurofilament expression as observed in the current case.1 The PNET-like elements also showed increased proliferation indices. The highly proliferative
PNET-like component may dictate the biological progression and therapeutic response in MG-PNETs. Perry et al. have demonstrated MYCN and MYCC amplification within the PNET-like areas of MG-PNETs in 33% and 10% of their cases, respectively.1 The present case exhibited polysomy of chromosomes 2 and 8 but no specific MYC gene amplification. MYC amplifications have also been reported by Behdad et al. in 52% of their CNS PNET cases and Kaplan et al. in their case report of a gliosarcoma with a PNET component.2,8 Interestingly, the current case demonstrated heterogenous EGFR immunostaining as well as heterogenous EGFR amplification with CISH. High level amplification of EGFR was relatively concentrated in a region of the glioblastoma component, with only rare amplified cells in other regions, including the PNET-like component. This unusual, relatively circumscribed nodule of EGFR-amplified glioma is reminiscent of the nodular amplification of MYC genes reported in the PNET-like components, and may indicate a predisposition to gene amplification via double minute formation in MG-PNETs in general. Intratumoural heterogeneity of EGFR amplification in GBM has been previously described previously by Okada et al.,9 but in this previous report amplification was seen primarily at the infiltrating edge of tumour. PNET-like elements in a GBM, as seen in the current case, raise very few differential diagnoses. Small cell GBMs may occasionally be encountered in similar settings.1 However, small cell GBM is characterised by deceptively bland round nuclei reminiscent of oligodendroglioma and typically lack hyperchromasia, anaplasia, and karyorhexis commonly present in PNET.10 Immunohistochemically, small cell GBMs are immunoreactive for GFAP and lack immunoreactivity for synaptophysin.1,10 The entities that would enter differential diagnostic considerations in the paediatric age group such as medulloblastoma or atypical teratoid/rhabdoid tumour would be distinctly unusual in an elderly patient.8,11,12 These paediatric tumours are also generally not associated with low grade glioma as seen in the current case. The median survival of MG-PNET has been documented to be 9.1 months, with frequent treatment failures.1 Metastases have been reported in 21% of cases with follow-up, including one case with metastasis to the bone marrow.1 The few patients who were switched to platinum-based chemotherapy following failure of irradiation or temozolomide showed radiological responses. These findings underscore the importance of close follow-up and surveillance for craniospinal dissemination, and consideration of platinum based chemotherapy as an alternative or adjunct to standard alkylating agent therapy. In summary, we present a relatively unusual case of GBMPNET in a 68-year-old male. The two components of this neoplasm possess distinct histomorphology, immunophenotype, and genetics, and each contributes to the clinical and prognostic features of GBM-PNET. The biological connotations and therapeutic ramifications of this distinction necessitate that both components of this tumour are recognised in the emerging diagnostic nomenclature and in clinical diagnostic neuropathology. Conflicts of interest and sources of funding: Dr Buckland is a Cancer Institute NSW Clinical Research Fellow. Karina Aivazian * Benjamin P. Jonker{ Adrienne Moreyjj
Copyright © Royal College of pathologists of Australasia. Unauthorized reproduction of this article is prohibited.
CORRESPONDENCE
Christina Selinger{ Ruta Gupta*§ Michael E. Buckland*§ *Discipline of Pathology, Sydney Medical School, University of Sydney, Sydney, Departments of {Neurosurgery, zTissue Pathology and Diagnostic Oncology, and §Neuropathology, Royal Prince Alfred Hospital, Sydney, and jjDepartment of Anatomical Pathology, St Vincent’s Hospital, Sydney, NSW, Australia Contact Dr R. Gupta. E-mail: [email protected] 1. Perry A, Miller CR, Gujrati M, et al. Malignant gliomas with primitive neuroectodermal tumour-like components: a clinicopathologic and genetic study of 53 cases. Brain Pathol 2009; 19: 81–90. 2. Kaplan KJ, Perry A. Gliosarcoma with primitive neuroectodermal differentiation: case report and review of the literature. J Neurooncol 2007; 83: 313–8. 3. Shibahara J, Fukayama M. Secondary glioblastoma with advanced neuronal immunophenotype. Virchows Arch 2005; 447: 665–8. 4. Yan H, Parsons DW, Jin G, et al. IDH1 and IDH2 mutations in gliomas. N Engl J Med 2009; 360: 765–73. 5. Capper D, Zentgraf H, Balss J, Hartmann C, von Deimling A. Monoclonal antibody specific for IDH1 R132H mutation. Acta Neuropathol 2009; 118: 599–601. 6. Balss J, Meyer J, Mueller W, Korshunov A, Hartmann C, von Deimling A. Analysis of the IDH1 codon 132 mutation in brain tumours. Acta Neuropathol 2008; 116: 597–602. 7. Gessi M, Setty P, Bisceglia M, et al. Supratentorial primitive neuroectodermal tumours of the central nervous system in adults: molecular and histopathologic analysis of 12 cases. Am J Surg Pathol 2011; 35: 573–82. 8. Behdad A, Perry A. Central nervous system primitive neuroectodermal tumours: a clinicopathologic and genetic study of 33 cases. Brain Pathol 2010; 20: 441–50. 9. Okada Y, Hurwitz EE, Esposito JM, Brower MA, Nutt CL, Louis DN. Selection pressures of TP53 mutation and microenvironmental location influence epidermal growth factor receptor gene amplification in human glioblastomas. Cancer Res 2003; 63: 413–6. 10. Perry A, Aldape KD, George DH, Burger PC. Small cell astrocytoma: an aggressive variant that is clinicopathologically and genetically distinct from anaplastic oligodendroglioma. Cancer 2004; 101: 2318–26. 11. Burger PC, Scheithauer BW, editors. Tumours of the Central Nervous System. Washington DC: American Registry of Pathology, 2007. 12. Louis D, Ohgaki H, Wiestler O, Cavanee W, editors. World Health Organization Classification of Tumours; Pathology and Genetics of Tumours of the Central Nervous System. 4th ed. Lyon: International Agency for Research on Cancer (IARC), 2007.
DOI: 10.1097/PAT.0b013e328351bceb
Neuroendocrine ductal carcinoma in situ, comedo type, of the breast detected by screening mammography: a potentially pre-invasive counterpart of high grade neuroendocrine tumours Sir, Neuroendocrine ductal carcinoma in situ (NE-DCIS), i.e., DCIS in which >50% of cells immunohistochemically express NE markers (chromogranin A and/or synaptophysin), has been regarded as a distinct variant of DCIS and a pre-invasive form of breast neuroendocrine tumour (NET).1–4 The pathognomonic clinical presentation of NE-DCIS is bloody nipple discharge
273
(72%) without a palpable mass (94%).3,4 Histologically, this tumour is characterised by a predominantly solid growth of carcinoma cells with low grade pathological findings including a low nuclear grade and no necrotic focus.1–3 To the best of our knowledge, this is the first case report of a comedo type NE-DCIS of relatively high nuclear grade, detected on mammography as abnormal calcifications. The patient was a 44-year-old premenopausal Japanese woman. She had been found to have abnormal calcification in her right breast by screening mammography and came to the Yamanashi University Hospital for a thorough examination of this lesion. She had no clinical symptoms. She had no medical or familial history of breast disease. Blood test results were unremarkable. Screening mammography revealed clusters of amorphous micro-calcification in the inner area of the right breast. On ultrasonographic examination, the calcified lesion appeared as hyperechoic spots within an irregularly-shaped hypoechoic area. From these diagnostic images, the patient was clinically suspected to have a DCIS. We performed ultrasound-guided, fine needle aspiration of the breast lesion after obtaining informed consent. The cytological diagnosis was ductal carcinoma. We performed a lumpectomy to remove the tumour. On the cut surface of the resected specimen from the right breast, a somewhat lobulated tumour mass, measuring 0.6 cm in diameter, was found in the deep portion of the mammary parenchyma. Histopathologically, this tumour was composed of a mostly solid growth of carcinoma cells involving some terminal duct-lobular units (TDLUs) (Fig. 1A). Necroses with dystrophic calcification were occasionally observed in the central areas of cancer cell nests (Fig. 1B). Carcinoma cells were polygonal or, sometimes, spindle-shaped and had finegranular, slightly eosinophilic cytoplasm (Fig. 1C). Their nuclei had irregular shapes with scattered nuclear grooves and a granular chromatin pattern, frequently with prominent nucleoli (Fig. 1C). Mitotic figures were common [22 per 10 high power field (HPF)]. Immunohistochemically, carcinoma cells were diffusely positive for synaptophysin (Fig. 2A) and focally positive for chromogranin A (Fig. 2B), but were negative for CD56 (NCAM). E-cadherin was clearly demonstrated in the cytoplasmic membranes of carcinoma cells (Fig. 2C). The nuclei showed strong oestrogen receptor (ER) and progesterone receptor (PgR) reactivity. The HER2 score was estimated to be 2þ and the Ki-67 (MIB-1) labelling index was 15.3%. Myoepithelial cells positive for smooth muscle actin and p63 were identified along the periphery of ducts and lobules filled with carcinoma cells. Based on these pathological findings, we considered this lesion to be intermediate to high grade NE-DCIS, comedo type, of the breast. Breast NE-DCIS, defined as a DCIS in which >50% of cancer cells express specific NE markers, has been regarded as a distinctive tumour entity with clinicopathological significance.1–4 Characteristic histological features of NE-DCIS include a predominantly solid growth of cancer cells and a well-developed vascular network. The presence of coagulation necrosis is fairly uncommon in this tumour and, to our knowledge, there have actually been no previous reports describing NE-DCIS which could be categorised as the comedo type. Recently, mammography has constituted by far the most important method of detecting early cancers, especially DCIS.5 Specific mammographic patterns, such as calcification and
Copyright © Royal College of pathologists of Australasia. Unauthorized reproduction of this article is prohibited.
CORRESPONDENCE
3. Regauer S, Nogales EF. Vulvar trichogenic tumors: a comparative study with vulvar basal cell carcinoma. Am J Surg Pathol 2005; 29: 479–84. 4. Braun-Falco M, Friedrichson E, Ring J. Subepidermal cleft formation as a diagnostic marker for cutaneous malignant melanoma. Hum Pathol 2005; 36: 412–5. 5. McNutt NS. Ultrastructural comparison of the interface between epithelium and stroma in basal cell carcinoma and control human skin. Lab Invest 1976; 35: 132–42. 6. Stanley JR, Beckwith JB, Fuller RP, Katz SI. A specific antigenic defect of the basement membrane is found in basal cell carcinoma but not in other epidermal tumors. Cancer 1982; 50: 1486–90. 7. Brenn T, McKee PH. Tumors of the hair follicle. Lazar AJF, McKee PH. Tumors and related lesions of the sebaceous glands. In: McKee PH, Calonje E, Granter SR. Pathology of the Skin. 3rd ed. Philadelphia: Mosby, 2005; 1260–1, 1313–4, 1543, 1559, 1586. 8. Carson FL, Lott RL. Microtomy. Carson FL. Fixation and processing. In: Brown RW. Histologic Preparation. Common Problems and Their Solutions. Illinois: CAP Press, 2009; 1–11, 15–25. 9. Ball NJ, Tanhuanco-Kho G. Merkel cell carcinoma frequently shows histologic features of basal cell carcinoma: a study of 30 cases. J Cutan Pathol 2007; 34: 612–9.
DOI: 10.1097/PAT.0b013e32835140d4
Glioblastoma with primitive neuroectodermal tumour-like components Sir, Central nervous system (CNS) tumours featuring areas of both high grade glioma and primitive neuroectodermal elements are rare and difficult to classify.1 They pose diagnostic and therapeutic challenges due to the presence of two components, each with distinct clinicopathological features, management principles, and prognoses.1 An additional problem is that these entities have been previously addressed in literature using variable terminology.2,3 A recent study of 53 patients, the largest to date, sought to clarify the nomenclature and biology of these neoplasms, and suggested a designation of ‘malignant glioma with primitive neuroectodermal tumour-like components (MG-PNET)’.1 We report a case of glioblastoma with PNET-like components (GBM-PNET), to our knowledge the first report of this entity in Australia. A 68-year-old male presented with a 6-week history of headaches and slurred speech. Magnetic resonance imaging
Pathology (2012), 44(3), April
(MRI) showed a large, partly cystic, peripherally enhancing mass centred in the right temporal lobe (Fig. 1A). The lesion caused superior displacement of the Sylvian fissure as well as compression of the midbrain by the uncus. The appearance was suggestive of a primary high grade neoplasm. A stereotactic right temporal craniotomy was performed with gross total resection of the lesion. Multiple fragments of grey-white tissue aggregating to 55 20 10 mm were received for histopathological examination. The entire macroscopic specimen was embedded for histopathological examination and revealed a large astrocytic neoplasm admixed with relatively circumscribed nodules of ‘small round blue cell tumour’ (Fig. 1B). The astrocytic component showed variable morphology, with regions of WHO grade II and III astrocytoma present, in addition to large areas of frank WHO grade IV glioblastoma (Fig. 2A–C). The astrocytic component was variably composed of pleomorphic fibrillary glial cells, as well as regions of gemistocytes with perivascular lymphocytic inflammation. Microvascular proliferation, mitotic activity, as well as geographic and pseudo-palisading necrosis were present. The nodules of ‘small round blue cell tumour’ consisted of cells with scanty cytoplasm and hyperchromatic ovoid to elongate nuclei with coarsely granular chromatin. Nuclear moulding, brisk mitotic activity, and karyorrhectic debris were present. Scattered anaplastic large cells with vesicular nuclei, prominent nucleoli, and multinucleated forms were also present (Fig. 2D–F). These relatively well circumscribed nodules resembled CNS PNET. Homer-Wright rosettes were not identified. Ancillary investigations included immunohistochemistry and in situ hybridisation (Fig. 3). The astrocytic component was diffusely and strongly immunoreactive for GFAP (Fig. 3A). EGFR immunoreactivity, though variable, was strong in the majority of the astrocytic component, including its infiltrating edge. p53 immunoreactivity was present in 50–60% of nuclei, and the proliferative index was up to 10% in the glioblastoma elements with Ki-67 labelling. The astrocytic component was not immunoreactive for synaptophysin, NSE, Neu-N, neurofilament or chromogranin, and showed moderate cell membrane immunoreactivity for CD56. In contrast, the PNET-like component showed diffuse strong cytoplasmic immunoreactivity for synaptophysin (Fig. 3B), CD56, and NSE, as well as weak patchy immunoreactivity
Fig. 1 (A) Peripherally enhancing, partly cystic mass centred in the right temporal lobe with a complex and irregularly enhancing soft tissue component on coronal T2 FLAIR MRI. Associated elevation of the Sylvian fissure, medial displacement of temporal lobe structures, and impingement on the brainstem by the uncus is seen. (B) GBM admixed with relatively circumscribed nodules of ’small round blue cell tumour’ (H&E).
Copyright © Royal College of pathologists of Australasia. Unauthorized reproduction of this article is prohibited.
CORRESPONDENCE
271
Fig. 2 (A) GBM with microvascular proliferation, and necrosis with peripheral pseudopalisading of nuclei (H&E). (B) Areas with gemistocytic differentiation (H&E). (C) Accompanying areas of hypercellularity with architectural and cytological atypia seen in low grade (WHO 2007 grade II) diffuse astrocytoma (H&E). (D) Admixed areas of PNET with prominent peritheliomatous growth pattern (H&E). (E) Elongate to ovoid, hyperchromatic nuclei of PNET with brisk mitotic activity (H&E). (F) Anaplastic large cells, with multinucleate forms in PNET-like components (H&E).
Fig. 3 (A) Strong, diffuse immunoreactivity for GFAP in the glioblastoma. (B) Strong, diffuse immunoreactivity for synaptophysin in PNET-like elements with nonimmunoreactivity in the adjacent GBM. (C) Focal EGFR gene amplification in GBM (inset: relative lack of EGFR amplification in PNET component) (CISH). (D) Representative FISH results; centromere 8 in green and MYCC in red. There are several copies of both red and green signals in most cells, indicating polysomy for chromosome 8 without specific MYCC amplification (FISH).
Copyright © Royal College of pathologists of Australasia. Unauthorized reproduction of this article is prohibited.
272
Pathology (2012), 44(3), April
CORRESPONDENCE
for Neu-N. Chromogranin and neurofilament were negative. The PNET-like elements lacked immunoreactivity for GFAP, which was restricted to rare single cells resembling entrapped glial cells. The proliferative index was 20–30% in these PNETlike areas with Ki-67 labelling, while p53 expression was seen in approximately 60–65% of nuclei. Immunoreactivity for EGFR was weak to absent in PNET-like areas. Both astrocytic and PNET components were non-immunoreactive for IDH1 (R132H). Fluorescent in situ hybridisation for MYCN and MYCC showed polysomy of chromosome 2 and chromosome 8, respectively, without amplification and with higher levels of polysomy seen in the PNET-like component. Chromogenic in situ hybridisation (CISH) for EGFR revealed an unusual pattern: there was high-level amplification of EGFR (>20 copies/cell) in a relatively circumscribed region of the glioblastoma component of the tumour (Fig. 3C), whilst other astrocytic areas contained only scattered (approximately 1–2%) individual cells with high level EGFR amplification. Rare single cells in the PNET component (<1%) also demonstrated high level EGFR amplification. Following surgical resection, the patient showed significant improvement, including resolution of headache and slurred speech. Spinal MRI showed no evidence of tumour dissemination. He is currently being managed with chemoradiotherapy as per the Stupp protocol.2 Platinum-based chemotherapy for CNS PNET has been reserved for recurrence or failure. The vast majority (>90%) of GBMs arise de novo without an underlying precursor lesion (primary glioblastomas), while the remainder have a history or histological evidence of a pre-existing low grade glioma (secondary glioblastoma). The GBM component in this case showed histological evidence of a secondary glioblastoma. Similar findings have been reported by Perry et al. and Shibahara et al. in their cases of MG-PNET.1,3 Perry et al. note that 89% of cases showed foci of diffuse astrocytoma on histology, with a significant subset also having a history of prior low grade glioma.1 They report a wide spectrum of lower grade glial elements, including fibrillary astrocytoma, gemistocytic differentiation, oligoastrocytoma, and oligodendroglioma, among others.1 Recently mutations in isocitrate dehydrogenase (IDH)-1 and -2 have been identified in 70–80% of low grade gliomas and secondary glioblastomas, and a sensitive and specific antibody to the most common mutant protein is now available.4,5 Interestingly, this tumour was negative for IDH1 (R132H). IDH1 mutations have been noted in a small proportion of supratentorial PNETs; however, the presence of IDH1 mutation in GBM-PNETs has not been investigated to date.6,7 The possibility that the emergence of PNET-like elements may preferentially occur in those secondary glioblastomas with wild-type IDH genes, or variant IDH mutations, remains to be examined. The histological features of the non-glial elements in this case were consistent with CNS PNET. The immunoreactivity for synaptophysin, NSE, and Neu-N confirmed their neuroectodermal lineage. The discrete nodular nature of the PNET-like elements was highlighted by immunoreactivity for synaptophysin (Fig. 3B) and NSE, and absence of GFAP immunoreactivity. Neu-N also showed patchy expression in these areas but not in the glioma components. Perry et al. demonstrated immunoreactivity for chromogranin in 29%, for Neu-N in 24% and for neurofilament in only 11% of their cases; thus a large majority of these tumours may lack chromogranin, and neurofilament expression as observed in the current case.1 The PNET-like elements also showed increased proliferation indices. The highly proliferative
PNET-like component may dictate the biological progression and therapeutic response in MG-PNETs. Perry et al. have demonstrated MYCN and MYCC amplification within the PNET-like areas of MG-PNETs in 33% and 10% of their cases, respectively.1 The present case exhibited polysomy of chromosomes 2 and 8 but no specific MYC gene amplification. MYC amplifications have also been reported by Behdad et al. in 52% of their CNS PNET cases and Kaplan et al. in their case report of a gliosarcoma with a PNET component.2,8 Interestingly, the current case demonstrated heterogenous EGFR immunostaining as well as heterogenous EGFR amplification with CISH. High level amplification of EGFR was relatively concentrated in a region of the glioblastoma component, with only rare amplified cells in other regions, including the PNET-like component. This unusual, relatively circumscribed nodule of EGFR-amplified glioma is reminiscent of the nodular amplification of MYC genes reported in the PNET-like components, and may indicate a predisposition to gene amplification via double minute formation in MG-PNETs in general. Intratumoural heterogeneity of EGFR amplification in GBM has been previously described previously by Okada et al.,9 but in this previous report amplification was seen primarily at the infiltrating edge of tumour. PNET-like elements in a GBM, as seen in the current case, raise very few differential diagnoses. Small cell GBMs may occasionally be encountered in similar settings.1 However, small cell GBM is characterised by deceptively bland round nuclei reminiscent of oligodendroglioma and typically lack hyperchromasia, anaplasia, and karyorhexis commonly present in PNET.10 Immunohistochemically, small cell GBMs are immunoreactive for GFAP and lack immunoreactivity for synaptophysin.1,10 The entities that would enter differential diagnostic considerations in the paediatric age group such as medulloblastoma or atypical teratoid/rhabdoid tumour would be distinctly unusual in an elderly patient.8,11,12 These paediatric tumours are also generally not associated with low grade glioma as seen in the current case. The median survival of MG-PNET has been documented to be 9.1 months, with frequent treatment failures.1 Metastases have been reported in 21% of cases with follow-up, including one case with metastasis to the bone marrow.1 The few patients who were switched to platinum-based chemotherapy following failure of irradiation or temozolomide showed radiological responses. These findings underscore the importance of close follow-up and surveillance for craniospinal dissemination, and consideration of platinum based chemotherapy as an alternative or adjunct to standard alkylating agent therapy. In summary, we present a relatively unusual case of GBMPNET in a 68-year-old male. The two components of this neoplasm possess distinct histomorphology, immunophenotype, and genetics, and each contributes to the clinical and prognostic features of GBM-PNET. The biological connotations and therapeutic ramifications of this distinction necessitate that both components of this tumour are recognised in the emerging diagnostic nomenclature and in clinical diagnostic neuropathology. Conflicts of interest and sources of funding: Dr Buckland is a Cancer Institute NSW Clinical Research Fellow. Karina Aivazian * Benjamin P. Jonker{ Adrienne Moreyjj
Copyright © Royal College of pathologists of Australasia. Unauthorized reproduction of this article is prohibited.
CORRESPONDENCE
Christina Selinger{ Ruta Gupta*§ Michael E. Buckland*§ *Discipline of Pathology, Sydney Medical School, University of Sydney, Sydney, Departments of {Neurosurgery, zTissue Pathology and Diagnostic Oncology, and §Neuropathology, Royal Prince Alfred Hospital, Sydney, and jjDepartment of Anatomical Pathology, St Vincent’s Hospital, Sydney, NSW, Australia Contact Dr R. Gupta. E-mail: [email protected] 1. Perry A, Miller CR, Gujrati M, et al. Malignant gliomas with primitive neuroectodermal tumour-like components: a clinicopathologic and genetic study of 53 cases. Brain Pathol 2009; 19: 81–90. 2. Kaplan KJ, Perry A. Gliosarcoma with primitive neuroectodermal differentiation: case report and review of the literature. J Neurooncol 2007; 83: 313–8. 3. Shibahara J, Fukayama M. Secondary glioblastoma with advanced neuronal immunophenotype. Virchows Arch 2005; 447: 665–8. 4. Yan H, Parsons DW, Jin G, et al. IDH1 and IDH2 mutations in gliomas. N Engl J Med 2009; 360: 765–73. 5. Capper D, Zentgraf H, Balss J, Hartmann C, von Deimling A. Monoclonal antibody specific for IDH1 R132H mutation. Acta Neuropathol 2009; 118: 599–601. 6. Balss J, Meyer J, Mueller W, Korshunov A, Hartmann C, von Deimling A. Analysis of the IDH1 codon 132 mutation in brain tumours. Acta Neuropathol 2008; 116: 597–602. 7. Gessi M, Setty P, Bisceglia M, et al. Supratentorial primitive neuroectodermal tumours of the central nervous system in adults: molecular and histopathologic analysis of 12 cases. Am J Surg Pathol 2011; 35: 573–82. 8. Behdad A, Perry A. Central nervous system primitive neuroectodermal tumours: a clinicopathologic and genetic study of 33 cases. Brain Pathol 2010; 20: 441–50. 9. Okada Y, Hurwitz EE, Esposito JM, Brower MA, Nutt CL, Louis DN. Selection pressures of TP53 mutation and microenvironmental location influence epidermal growth factor receptor gene amplification in human glioblastomas. Cancer Res 2003; 63: 413–6. 10. Perry A, Aldape KD, George DH, Burger PC. Small cell astrocytoma: an aggressive variant that is clinicopathologically and genetically distinct from anaplastic oligodendroglioma. Cancer 2004; 101: 2318–26. 11. Burger PC, Scheithauer BW, editors. Tumours of the Central Nervous System. Washington DC: American Registry of Pathology, 2007. 12. Louis D, Ohgaki H, Wiestler O, Cavanee W, editors. World Health Organization Classification of Tumours; Pathology and Genetics of Tumours of the Central Nervous System. 4th ed. Lyon: International Agency for Research on Cancer (IARC), 2007.
DOI: 10.1097/PAT.0b013e328351bceb
Neuroendocrine ductal carcinoma in situ, comedo type, of the breast detected by screening mammography: a potentially pre-invasive counterpart of high grade neuroendocrine tumours Sir, Neuroendocrine ductal carcinoma in situ (NE-DCIS), i.e., DCIS in which >50% of cells immunohistochemically express NE markers (chromogranin A and/or synaptophysin), has been regarded as a distinct variant of DCIS and a pre-invasive form of breast neuroendocrine tumour (NET).1–4 The pathognomonic clinical presentation of NE-DCIS is bloody nipple discharge
273
(72%) without a palpable mass (94%).3,4 Histologically, this tumour is characterised by a predominantly solid growth of carcinoma cells with low grade pathological findings including a low nuclear grade and no necrotic focus.1–3 To the best of our knowledge, this is the first case report of a comedo type NE-DCIS of relatively high nuclear grade, detected on mammography as abnormal calcifications. The patient was a 44-year-old premenopausal Japanese woman. She had been found to have abnormal calcification in her right breast by screening mammography and came to the Yamanashi University Hospital for a thorough examination of this lesion. She had no clinical symptoms. She had no medical or familial history of breast disease. Blood test results were unremarkable. Screening mammography revealed clusters of amorphous micro-calcification in the inner area of the right breast. On ultrasonographic examination, the calcified lesion appeared as hyperechoic spots within an irregularly-shaped hypoechoic area. From these diagnostic images, the patient was clinically suspected to have a DCIS. We performed ultrasound-guided, fine needle aspiration of the breast lesion after obtaining informed consent. The cytological diagnosis was ductal carcinoma. We performed a lumpectomy to remove the tumour. On the cut surface of the resected specimen from the right breast, a somewhat lobulated tumour mass, measuring 0.6 cm in diameter, was found in the deep portion of the mammary parenchyma. Histopathologically, this tumour was composed of a mostly solid growth of carcinoma cells involving some terminal duct-lobular units (TDLUs) (Fig. 1A). Necroses with dystrophic calcification were occasionally observed in the central areas of cancer cell nests (Fig. 1B). Carcinoma cells were polygonal or, sometimes, spindle-shaped and had finegranular, slightly eosinophilic cytoplasm (Fig. 1C). Their nuclei had irregular shapes with scattered nuclear grooves and a granular chromatin pattern, frequently with prominent nucleoli (Fig. 1C). Mitotic figures were common [22 per 10 high power field (HPF)]. Immunohistochemically, carcinoma cells were diffusely positive for synaptophysin (Fig. 2A) and focally positive for chromogranin A (Fig. 2B), but were negative for CD56 (NCAM). E-cadherin was clearly demonstrated in the cytoplasmic membranes of carcinoma cells (Fig. 2C). The nuclei showed strong oestrogen receptor (ER) and progesterone receptor (PgR) reactivity. The HER2 score was estimated to be 2þ and the Ki-67 (MIB-1) labelling index was 15.3%. Myoepithelial cells positive for smooth muscle actin and p63 were identified along the periphery of ducts and lobules filled with carcinoma cells. Based on these pathological findings, we considered this lesion to be intermediate to high grade NE-DCIS, comedo type, of the breast. Breast NE-DCIS, defined as a DCIS in which >50% of cancer cells express specific NE markers, has been regarded as a distinctive tumour entity with clinicopathological significance.1–4 Characteristic histological features of NE-DCIS include a predominantly solid growth of cancer cells and a well-developed vascular network. The presence of coagulation necrosis is fairly uncommon in this tumour and, to our knowledge, there have actually been no previous reports describing NE-DCIS which could be categorised as the comedo type. Recently, mammography has constituted by far the most important method of detecting early cancers, especially DCIS.5 Specific mammographic patterns, such as calcification and
Copyright © Royal College of pathologists of Australasia. Unauthorized reproduction of this article is prohibited.