Postirradiation mixed müllerian tumors of the uterus: a comparative clinicopathologic study.

Nine patients with mixed müllerian tumors (MMT) of the uterus associated with a history of prior pelvic irradiation were compared clinically and pathologically with 8 nonirradiation-associated MMT control patients. Patients with postirradiation tumors presented at a younger age and with symptoms indicative of extensive intraabdominal disease while the nonirradiation-associated control patients were initially evaluated for abnormal uterine bleeding only. Two-thirds of the postirradiation patient's neoplasms were classified as heterologous MMT (mixed mesodermal tumor) whereas 62% of the control patient's neoplasms were homologous MMT (carcinosarcoma). Regardless of clinical presentation or histologic composition both groups fared equally poorly with average survival times of six and seven months, respectively. We were unable to substantiate that some histologic components of uterine MMT denote a poorer prognosis than others or that the postirradiation MMT behaves any differently, in the course of time, from the sporadic type. When uterine MTT is encountered in a patient under 55 years of age, the possibility that pelvic irradiation was administered some years before should be raised.