The perivascular epithelioid cell family of tumors (PEComas) includes angiomyolipoma, lymphangioleiomyomatosis, clear-cell "sugar" tumor of the lung and a variety of extrapulmonary epithelioid and spindle-cell tumors referred to by various names. PEComas are now widely recognized histologically, and have been reported to occur at most anatomical sites, including the female genital tract. However, a distinctive variant of PEComa, designated "sclerosing PEComa," has only recently been described in the literature. All 13 of the cases of sclerosing PEComa reported thus far have been in women (mean age of 49 y), with a predilection for the retroperitoneum. Only one of the reported cases showed transition to a high-grade malignant phenotype. We report the first case of sclerosing PEComa arising in the uterine adnexa, with high-grade malignant transformation.