MALIGNANT PLEXIFORM TUMOR OF THE UTERUS - AN UNUSUAL VARIANT OF EPITHELIOID LEIOMYOSARCOMA

A 46-year-old woman with the complaint of hypermenorrhea underwent hys terectomy for a presumed uterine myoma. The solid tumor in the myometr ium was gray in color, was 4 cm in diameter, and showed hemorrhage and necrosis, Histologicaily, the tumor consisted of round or polygonal c ells arranged in cords and nests, and its histological features closel y resembled those of plexiform tumor which has been reported as a beni gn, epithelioid smooth muscle tumor of the uterus. In the tumor in our patient, however, mild nuclear atypia and two to three mitoses/10 hig h-power fields were present. Two months after the hysterectomy, the pa tient was found to have metastatic foci in the lumbar vertebrae and il iac bone, which contained tumor cells with the same histological featu res, Accordingly, the present tumor might be interpreted as a malignan t plexiform tumor of the uterus, an unusual variant of epithelioid lei omyosarcoma. (C) 1996 Academic Press, Inc.