ANGIOMYOFIBROBLASTOMA OF THE FEMALE GENITAL-TRACT - ANALYSIS OF 17 CASES INCLUDING A LIPOMATOUS VARIANT

The clinicopathological and immunohistochemical profile of 17 cases of angiomyofibroblastoma (AMF) arising in the genital tract of females i s reported. The lesions usually presented as painless masses and were located in the superficial vulvar region (15 cases), canal of Nuck (on e case), and perineum (one case) in women ranging in age from 38 to 60 years (median, 46 years). The tumors were well delineated and ranged in size from 2 to 8 cm in greatest dimension. Microscopically, they we re composed of spindled and epithelioid mesenchymal cells arranged in cords and nests preferentially arrayed around numerous small to medium -sized vessels. Mitotic activity ranged from 0 to 7 mitoses per 50 hig h-power fields (HPF) with no abnormal mitotic figures. Minimal nuclear atypia was appreciated. Intralesional fat was present in 12 cases and in two of these cases constituted most of the tumor (lipomatous varia nt of AMF). Tumor cells expressed vimentin (five of five cases), estro gen receptor protein (six of six cases), progesterone receptor protein (five of six cases), desmin (six of eight cases), CD34 (one of six ca ses), and smooth muscle actin (one of seven cases). None of the eight women with follow-up of up to 25 years (mean, 7.8 pars) after simple e xcision developed a recurrence. This study confirms the benign nature of AMF, broadens its morphological spectrum to include a lipomatous va riant, and proposes an origin from a perivascular stem cell that is ca pable of myofibroblastic and fatty differentiation. Copyright (C) 1997 by W.B. Saunders Company.