The management of 540 patients with the diagnoses of “pelvic mass/uterine leiomyomata” was reviewed with respect to preoperative evaluation, surgical procedures, and final pathologic diagnosis. Approximately 6170 patients were admitted to the Gynecology Service at St. Luke's- Roosevelt Hospital Center from July 1984 to June 1985. During this period, 36 of 432 diagnostic laparoscopies (8.3%) and 503 of 1666 laparotomies (30.2%) were performed to evaluate or treat these women. The final diagnoses in the 249 patients admitted with the impression of leiomyomata were: leiomyomata, 235 (94.4%); benign adnexal masses, seven (2.8%); cancers, four (1.6%); and miscellaneous, three (1.2%). Of the 291 patients evaluated for pelvic mass, the findings were: benign ovarian or tubal cysts, 98 (33.7%); leiomyomata, 42 (14.4%); cancers, 40 (13.7%); benign cystic teratomas, 38 (13.1%); endometriosis, 28 (9.6%); miscellaneous, 23 (7.9%); and pelvic inflammatory disease, 22 (7.6%). Correlation between the patient's age, preoperative impression, and final diagnosis is presented with particular attention to the 44 patients (8.1%) in whom malignancy was found. All the possibilities that such masses may represent must be considered preoperatively, and the patient be informed of her risk of malignancy.