Eight clinical and paraclinical parameters were investigated in a retrospective study of 100 patients who underwent operations for adenocarcinoma of the endometrium and compared to the vaginal cytology prior to treatment. The over-all accuracy of vaginal cytology was 61%. In advanced stages, with increasing dedifferentiation of the tumour and especially in cases which later showed evidence of cervical invasion microscopically, the accuracy was higher. Previous pregnancies and deliveries showed no influence on the cytological accuracy. Positive vaginal cytology was the only positive diagnostic sign for cancer in only three of the 100 cases.