Pigmented perivascular epithelioid cell tumor of the skin: first case report

The authors present a first case of pigmented perivascular epithelioid cell tumor (PEComa) of the skin, which was misdiagnosed histopathologically as metastatic melanoma. PEComa are exceedingly rare neoplasms, and only a few cases have been reported in kidney, liver, and pelvis. Herein, we describe this very rare entity in the subcutaneous tissue of the flank with very similar if not identical morphology of renal clear cell carcinoma. Because of the presence of focal melanin pigmentation and strong positivity for HMB-45, the lesion was mistaken for metastatic melanoma. To the best of authors' knowledge, this is the first case of cutaneous PEComa with melanin pigmentation. Awareness about occurrence of the lesion in the subcutaneous tissue and its unique immunoprofile would be helpful to reach correct diagnosis and to distinguish this lesion from melanoma or metastatic renal clear cell carcinoma.