Objective: The object of this study was to assess the association of histologic, cytokinetic, and molecular variables in preoperative endometrial samples with extrauterine disease, recurrence, and survival among patients with endometrial cancer. Study Design: In a case-cohort study of 125 women, ploidy, S-phase fraction, proliferative index, deoxyribonucleic acid index, proliferating cell nuclear antigen, MIB-1 proliferation marker, p53 tumor suppressor gene, and cytoplasmic HER-2/neu oncogene and bcl-2 expressions were quantitated. Results: A model with only one independent term predicted progression-free survival; that variable was p53 (P <.0001; relative risk, 5.60). A model with two independent terms predicted disease-related survival; these variables were p53 (P =.0002; relative risk, 7.39) and MIB-1 (P =.03; relative risk, 3.27). Among patients with tumors with both p53 and MIB-1 expression exceeding 33%, a total of 32% had died of disease by 2 years. A model for predicting extrauterine disease selected two independent variables: p53 (odds ratio, 3.20; P =.01) and ploidy (odds ratio, 2.16; P =.04). An advanced surgical stage was encountered in 26% to 35% of cases in which either the p53 expression exceeded 33% or the deoxyribonucleic acid content was nondiploid and in 53% of cases in which both variables were unfavorable. Conclusions: Preoperative evaluation of quantifiable cytokinetic and molecular variables can assist in identifying tumor types that are predisposed toward a more aggressive clinical course. (Am J Obstet Gynecol 2000;182:1535-44.)