Primary renal myoepithelial carcinoma is an exceedingly rare neoplasm with an aggressive phenotype and Ewing sarcoma breakpoint region 1 (EWSR1) rearrangement in a small fraction of cases. In addition to its rarity, the diagnosis can be challenging for the pathologist due to morphologic heterogeneity, particularly on the biopsy specimen. At times, immunohistochemistry may be indecisive; therefore, molecular studies should be undertaken for clinching the diagnosis. We aim to illustrate a case of primary myoepithelial carcinoma of the kidney with EWSR1-rearrangement in a 67-year-old male patient who presented with right supraclavicular mass, which was clinically diagnosed as carcinoma of an unknown primary. An elaborate immunohistochemical work-up aided by fluorescent in-situ hybridization allowed us to reach a conclusive diagnosis. This unusual case report advocates that one should be aware of the histological mimickers and begin with broad differential diagnoses alongside sporadic ones and then narrow them down with appropriate ancillary studies.
Cutaneous myoepithelial neoplasms and papillary eccrine adenomas (PEA) are rare conditions. Malignant tumors within a PEA are even rarer, with only one case reported to date.
Herein, we present an extremely rare case of a cutaneous myoepithelial carcinoma arising in a PEA in a 70-year-old man presenting a solid mass in the left buttock.
Histopathologically, most of the resected tumor revealed features consistent with the diagnosis of PEA. Some small nests and nodules were intermixed with the PEA and were present adjacent to the PEA. The tumor cells of nests and nodules showed ovoid to spindle shaped nuclei and slightly eosinophilic cytoplasm. Immunohistochemically, they were positive for both epithelial and myogenic markers, consistent with myoepithelioma. An inguinal lymph node with a metastatic lesion showed the same findings of myoepithelioma despite inconspicuous atypia. Our case showed malignant transformation of the myoepithelial cells at the outermost layers of the PEA.
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Papillary eccrine adenoma associated with syringocystadenoma papilliferum Neha Meena, PrafullaKumar Sharma, Sawan Kumar, Minakshi Bhardwaj Indian Journal of Dermatology, Venereology and Leprology.2018; 84(3): 322. CrossRef
Pleural fluid metastases of myoepithelial carcinoma: A case report and review of the literature Alicia Calderon Bhambra, Yanhong Zhang, Eric C. Huang, John Bishop, Mahan Matin, Alaa Afify CytoJournal.2016; 13: 13. CrossRef
Epithelial-myoepithelial carcinoma (EMC) is a rare low grade malignant tumor of the salivary glands and it shows a characteristic biphasic population of epithelium and myoepithelium. It shows various cytologic and histologic features, so making an exact diagnosis is difficult. We report here on two cases of epithelial-myoepithelial carcinoma arising from the parotid gland and we compare the cytologic findings of the aspirated samples with the histologic findings of the tumors. We think the finding of mixed pattern of large, clear myoepithelia and small epithelia is the most valuable finding in the diagnosis of EMC.
Epithelial-myoepithelial carcinoma (EMC) is a low grade malignant neoplasm that commonly occurs in the parotid gland. Recently, we investigated a case of EMC that occurred in the external auditory canal (EAC) in a 35-year-old male, and this tumor was initially diagnosed as pleomorphic adenoma. The difficulty associated with diagnosing EMC by aspiration cytology arises from both the rare incidence of this tumor and the overlapping spectrum of cytological features found in various salivary gland tumors, such as pleomorphic adenoma, basal cell adenoma and adenoid cystic carcinoma.
Epithelial-myoepithelial carcinoma is an uncommon, low grade malignant epithelial neoplasm and metastasis is exceedingly rare. This article highlights the fine needle aspiration cytology(FNAC) of a case of metastatic epithelial-myoepithelial carcinoma of the scalp. A 51-year-old female presented with the left parietotemporal scalp mass two months after the left parotidectomy for epithelial-myoepithelial carcinoma. FNAC from the scalp mass showed a biphasic population of ductal epithelial and myoepithelial origin. These epithelial aggregates were numerous and formed a distinct three dimensional architecture in the background of numerous naked nuclei. The three dimensional architectures were predominantly composed of tightly cohesive eosinophilic ductular epithelial cells which tended to aggregate, overlap, and form tubules. Clear myoepithelial cells in three dimensional tissue fragment were inapparent and a few were attached to the periphery of the fragments. A few myoepithelial cells with clear abundant vaculoated cytoplasm were found in the foamy background. The cytological diagnosis was metastatic epithelial-myoepithelial carcinoma. The histologic findings of the scalp mass were those of typical epithelial-myoepithelial carcinoma. Cytologic distinction of epithelial-myoepithleial carcinoma, pleomorphic adenoma, and adenoid cystic carcinoma may be very difficult but careful attention to clinical features and cellualr details can classify these neoplasms correctly.
Epithelial-myoepithelial carcinoma(EMC) is a rare, low grade malignant tumor of the salivary glands. The EMC has a distinctive histological appearance comprising ductal structures with an inner epithelial cell component and an outer layer of myoepithelial cells which show plump clear cytoplasm. The cytologic features of the EMC have been rarely described. A correct cytological diagnosis to this rare tumor is difficult with high false negative rate. We report a case of EMC in which fine needle aspiration cytologic findings were misinterpreted as a pleomorphic adenoma.
Epithelial-myoepithelial carcinoma of intercalated duct(origin) is a recently described tumor characterized by its typical biphasic pattern of central duct like cell and peripheral clear cell. We described a case of epithelial-myoepithelial carcinoma in a 10-year-old boy.
Microscopically, the tumor showed typical biphasic pattern, diffuse proliferation of clear cells and linining epithelial cells of tubular structures. Immunohistochemically, the clear cell showed positive reaction to S-100 protein, and the epithelial cells expressed cytokeratin indicating myoepithelial and epithelial differentiation respectively.
Biphasic differentiation of the tumor cells could be also proved by electronmicroscopic study.