Perivascular epithelioid cell tumours of the genitourinary tract: clinicopathological features and molecular...

Perivascular epithelioid cell tumours (PEComas) comprise a distinctive and biologically heterogeneous family of mesenchymal neoplasms defined by perivascular epithelioid differentiation and dual melanocytic and smooth muscle-like immunophenotypes. Within the genitourinary (GU) tract, renal tumours are historically designated as angiomyolipoma (AML) and represent the most common and biologically informative manifestation of PEComa, serving as the conceptual reference model for understanding PEComa across different organ sites. Extrarenal GU PEComas, on the other hand, are rare, morphologically diverse and frequently pose significant diagnostic challenges, particularly in limited biopsy material. This review synthesizes contemporary clinicopathological, immunohistochemical and molecular data on GU PEComas, with emphasis on diagnostic pathology, risk stratification and practical diagnostic interpretation. This also emphasizes classification based on shared molecular drivers rather than organ site or legacy terminology and provides a guide for accurate diagnosis, risk assessment and interpretation of PEComas in daily pathology practice.