The morphologic spectrum of uterine PEC-cell associated tumors in a patient with tuberous sclerosis.

Perivascular epithelioid cell (PEC) neoplasms are an unusual group of mesenchymal tumors thought to arise from the PEC, which characteristically expresses melanocytic markers with common coexpression of muscle markers. They show a wide morphologic spectrum and have been described in multiple anatomical locations, including the uterus. We report a 59-year-old woman with tuberous sclerosis, initially diagnosed with a uterine malignant mixed müllerian tumor, in whom the hysterectomy specimen also showed 3 other incidental tumors: a subserosal angiomyolipoma consisting of blood vessels of varying caliber, mature adipose tissue, and nests of spindle cells arranged in a perivascular location, a sclerosing PEComa consisting of small nests of clear epithelioid cells present in a background of marked sclerosis centered in the lower uterine segment/endocervix, and diffuse lymphangiomyomatosis involving the endocervix, lower uterine segment, and uterine corpus. This case provides further evidence of a common precursor cell of origin for these lesions.