PEComa of the urinary bladder.

Perivascular epithelioid cell tumors are a family of related mesenchymal neoplasms that include angiomyolipoma, lymphangiomyomatosis, clear cell sugar tumor of the lung and a group of rare morphologically and immunophenotypically similar lesions that show immunoreactivity for both melanocytic (HMB-45 and/or melan-A) and smooth muscle (actin and/or desmin) markers. This case is presented for its rare occurrence and characteristic morphologic and immunohistochemical features.