title: Malignant perivascular epithelioid cell tumor ('PEComa'): a case report and literature review of cutaneous/subcutaneous presentations.
abstract: Perivascular epithelioid cell (PEC) tumors, also called 'PEComas,' are distinct tumors showing PEC differentiation with characteristic histologic and immunophenotypic features. PEComas are rare tumors documented in the literature presenting in numerous anatomic sites including the thorax, abdomen, pelvis, soft tissue and skin. Criteria for malignancy does not exist for the subset of PEComas that pursue an aggressive clinical course. Herein, we present an unusual case of a malignant PEC tumor presenting as a scalp nodule in a patient with a prior diagnosis of 'melanoma' based upon the immunophenotypic profile of an excised enlarged cervical lymph node. The purpose of this case presentation is to further describe the rare clinical manifestations of a subcutaneous PEC tumor, emphasize the malignant potential of this entity, and review the literature focusing upon clinicopathologic features of cutaneous/subcutaneous PEComas.
authors.affiliation: Department of Pathology University of South Florida College of Medicine, Tampa, FL, USA. kcalder@hsc.usf.edu
authors.forename: Kenneth B
authors.initials: KB
authors.lastname: Calder
authors.forename: Scott
authors.initials: S
authors.lastname: Schlauder
authors.forename: Michael B
authors.initials: MB
authors.lastname: Morgan
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D003937:Diagnosis, Differential; D015622:Epithelioid Cells / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008297:Male; D008545:Melanoma / Q000175:diagnosis / Q000556:secondary; D018204:Neoplasms, Connective and Soft Tissue / Q000175:diagnosis* / Q000378:metabolism; D012535:Scalp / Q000378:metabolism / Q000473:pathology; D012878:Skin Neoplasms / Q000175:diagnosis; D018235:Smooth Muscle Tumor / Q000175:diagnosis* / Q000378:metabolism / Q000556:secondary
chemical_list: D014408:Biomarkers, Tumor