Objective. The purpose of this paper was to evaluate the agespecific survival for women diagnosed with endometrioid adenocarcinoma of the uterus. Methods. A retrospective analysis was conducted of 328 patients diagnosed with endometrioid adenocarcinoma of the uterus between January 1990 and December 1997. Patients were followed for 3 to 96 months with a mean of 43 months. The impact of age on survival was assessed using Cox proportional hazard regression and multivariate analysis for age, stage, and grade. Stage and grade were analyzed using log-rank tests, and survival curves were generated by the Kaplan-Meier method. Results. A total of 328 patients were evaluated. Multivariate analysis revealed age, stage, and grade were all significant independent predictors of survival (P < 0.0001). Age-specific survival varied from a high of 90% at age 40 to a low of 55% at age 80. Interval age-specific survival decreased below 86% at age 50. Subset analysis of patients younger than 50 compared with older patients revealed no difference in surgical stage or grade of tumors among these patients. Patients older than 50, however, were 41% more likely to receive adjuvant radiation therapy. Conclusion. Age is a specific, significant predictor of outcome in endometrioid adenocarcinoma of the uterus. Survival decreases significantly in patients older than 50. This decreased survival associated with age is unrelated to surgical stage or grade of adenocarcinoma. Decreased survival could involve molecular differences in the developing endometrial cancer or an increased risk of death from other non-cancer-related factors. (C) 2000 Academic Press.