RESUMO
One hundred women who had surgical intervention indicated for pelvic masses, were studied prospectively, all of them were investigated and treated in the obstetrical and gynecology Department of the Hospital del Salvador between January 1988 to January 1989. Pelvic tumors were classified following the scheme at the University of Tokyo's Obstetrician and Gynecology Department, which was designated to correlate the echographic image with the tumors histology and especially to distinguish preoperatively the benign or malign nature of the mass. The early diagnosis of ovarian cancer in the general population was not the objective. The classification divides the tumors in 6 groups with two o three subgroups for each one of them the probability of the tumors being benign was high for those in the group one to four (the predictive value of non malignancy was 98.4%) and the possibility of malignancy was high especially in the group 6 (the predictive value for malignancy was 63.6%).