The International Federation of Gynecology and Obstetrics (FIGO) adopted surgical staging criteria in 1988. Many studies have shown that histologic grade, nuclear grade, lymph-vascular space invasion and cell type are also important predictors of survival. It has not been clarified, however, how to integrate these histopathologic variables into the process of estimating individual prognosis. We performed Cox multivariate regression analysis to create models that incorporate various histopathologic factors for estimating the prognoses of patients with endometrioid adenocarcinoma of the uterine corpus. Our study was based on data from 206 patients who underwent complete surgical staging, including systematic pelvic and para-aortic lymph node dissection. Two models resulted: one included depth of myometrial invasion, para-aortic node metastasis and the number of sites involved by the tumor among the cervix, ovary and pelvic lymph nodes (which we designated as extracorporeal spread score, ECS) and the other incorporated nuclear grade and lymph-vascular space invasion as variables. These 2 models enabled the prognosis for patients with endometrioid adenocarcinoma to be stratified into several levels according to hazard ratio. Comprehensive integration of the histopathologic prognostic factors, categorized into those relating to tumor extent and those relating to tumor virulence, should facilitate the estimation of individual prognosis more accurately than FIGO staging alone.