Determinants of survival of surgically staged patients with endometrial carcinoma histologically confined to the uterus: implications for therapy.

OBJECTIVE: To determine the factors that influence the survival of patients with endometrial carcinoma histologically confined to the uterus.
METHODS: Retrospective analysis was conducted of 262 surgically staged cases using multiple regression (Cox proportional hazards model).
RESULTS: After excluding patients with clear-cell and serous tumors, which were adverse prognostic factors unrelated to any other variables, we found that survival was adversely affected by increasing stage, tumor grade and depth of myometrial invasion, cervical stromal and vascular space invasion by tumor, and increasing age. Tumor grade, myometrial invasion, and cervical involvement by tumor exerted their effects on survival as dichotomous rather than as ordinal variables. The greatest effect on survival was obtained by dichotomizing grade as grade 3 versus grade 1 or 2, myometrial invasion as invasion of more versus less than the inner third of the myometrium, and cervical spread as the presence versus absence of stromal invasion. The joint effect of the tumor-related prognostic factors was best expressed by constructing three risk groups consisting of patients with zero or one, two, and three or four risk factors. These risk groups were associated with 5-year survival rates of 97, 66, and 17%, respectively. After adjustment for risk factors, pelvic radiation did not affect survival significantly, although there was a trend toward improved survival of subjects with two risk factors who received pelvic radiation (70 versus 50% survival at 5 years).
CONCLUSIONS: The number of tumor-related risk factors present is the best predictor of survival of patients with endometrial carcinoma confined to the uterus, and may provide the optimal basis for individualization of treatment.