The Ohio State University Registry recorded 1208 uterine corpus malignancies between 1940 and 1983. Thirty cases occurred in women with a history of pelvic irradiation. Eight patients had previously been irradiated for pelvic malignancy, four of whom presented with advanced stage sarcomas and died of their disease within 14 months. This represents an increase over the expected sarcoma prevalence which is less than 5%. In contrast, the majority of women (20 of 22) previously irradiated for benign conditions were diagnosed with endometrial adenocarcinoma. In 18, the adenocarcinoma was diagnosed as Stage I, and the prognosis was only slightly less favorable than for nonirradiated women. No significant effect of age at the time of irradiation was apparent. This study of women with a history of pelvic irradiation who later developed uterine cancer demonstrates a tendency for patients previously irradiated for pelvic ma-lignancy to present with advanced stage, extremely aggressive uterine tumors compared to those previously irradiated for benign conditions.