Primary cutaneous PEComa.
A 48-year-old woman attended a physician because of a solitary cutaneous nodule on the left lower leg. Microscopic examination of the excisional specimen revealed a dermal tumor composed of nests of epithelioid cells exhibiting clear cytoplasm. They had centrally located vesicular nuclei with distinct nucleoli. A rich network of capillaries was present throughout. The tumor showed an infiltrative border. There was no epidermal involvement. Periodic acid-Shif (PAS) and PAS-Diastase stains demonstrated glycogen deposition within the cytoplasm of the clear cells. Immunohistochemical evaluation revealed that the tumor cells were positive for HMB-45 and microftalmia associated transcription factor (MITF). Focal desmin positivity was also seen. The tumor cells were negative for S-100 protein, alfa smooth muscle actin, HHF-35, and various cytokeratins. The case is one of a primary cutaneous pecoma. Pecomas are rare, recently described mesenchymal tumors composed of perivascular epithelioid cells. They constitute a spectrum of lesions in different organs including angiomyolipoma of the kidney and liver, sugar tumor of the lung, lymphangiomatosis, and lymphangiomyoma. Primary cutaneous PEComas are exceptionally rare and have only recently been recognized. To date, these are approximately 22 cases in the English literature. Follow-up data is limited but they appear to behave in a benign fashion. We report an additional case with the goal of alerting dermatopathologists to this distinctive unusual neoplasm.
Chaplin
Anna
A
From the *Division of Anatomical Pathology, Dalhousie University, Halifax, Nova Scotia, Canada; †Department of Pathology, Valley Regional Hospital, Kentville, Nova Scotia, Canada; and ‡Department of Patholgy, Colchester Regional Hospital, Truro, Nova Scotia, Canada.
Conrad
David M
DM
Tatlidil
Cuneyt
C
Jollimore
Jason
J
Walsh
Noreen
N
Covert
Alan
A
Pasternak
Sylvia
S
D000951:Antigens, Neoplasm / Q000032:analysis; D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D003893:Desmin / Q000032:analysis; D005260:Female; D006801:Humans; D007866:Leg; D058950:Melanoma-Specific Antigens; D051739:Microphthalmia-Associated Transcription Factor / Q000032:analysis; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000032:analysis; D054973:Perivascular Epithelioid Cell Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D012878:Skin Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D016896:Treatment Outcome
D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D003893:Desmin; C497234:MITF protein, human; D058950:Melanoma-Specific Antigens; D051739:Microphthalmia-Associated Transcription Factor; D009363:Neoplasm Proteins