The many faces of perivascular epithelioid cell tumors: case series illustrating the spectrum of a rare mesenchymal tumor.

Perivascular epithelioid cell tumors (PEComas) are rare mesenchymal neoplasms composed of distinctive perivascular epithelioid cells that exhibit both melanocytic and smooth muscle differentiation on immunohistochemistry. These tumors can develop in various anatomic locations and display variable biological behavior ranging from benign to aggressive malignant disease. We present a case series of four patients diagnosed with PEComa at different anatomic sites. Histopathological analysis in all cases demonstrated characteristic epithelioid or spindle-shaped morphology, with some cases showing positive staining for melanocytic markers such as HMB-45 and Melan-A, as well as smooth muscle markers. Due to their rarity, definitive management protocols are not yet well established. Surgical resection remains the primary treatment for localized disease, while systemic therapies targeting the mammalian target of rapamycin pathway may be considered for unresectable tumors or metastatic disease. This case series underscores the heterogeneity of PEComas and highlights the importance of multidisciplinary management and long-term follow-up.