The concentrations of progesterone receptors in endometrial tumors of 160 patients were analyzed with respect to survival and presence of clinicopathologic prognostic factors. The concentration of 25 fmol/mg of proteins for progesterone receptors appeared to be most powerful for prediction of survival. The survival was also significantly correlated to age, depth of myometrial invasion and clinical stage of the tumor. Concentration of estrogen receptors could not be correlated with the probability of patients' actuarial survival.