The malignant potential of small cystic ovarian tumors in women over 50 years of age

Objective. The aim of this study was to determine the risk of malignancy in cystic ovarian tumors <10 cm in diameter in asymptomatic postmenopausal women or women ≤50 years of age. Methods. All cystic ovarian tumors detected by transvaginal sonography screening in asymptomatic postmenopausal women or women ≤50 years of age were evaluated with respect to size and morphology. Histology was recorded on all tumors removed surgically. Follow-up data were available both on patients undergoing surgery and on those who elected to be followed without operative intervention. Results. Unilocular cystic tumors were detected in 256 of 7705 patients (3.3%). All tumors were <10 cm in diameter and 90% were <5 cm in diameter. One hundred twenty-five of these cysts (49%) resolved spontaneously within 60 days and 131 (51%) persisted. Forty-five patients with persisting ovarian cysts underwent operative removal of these tumors. Thirty-two patients had ovarian serous cystadenomas, and the remainder had a variety of benign lesions. There were no cases of ovarian carcinoma in this group. Eighty-six patients with unilocular cystic ovarian tumors were followed at 3- to 6-month intervals without surgery, and none have developed ovarian cancer. Complex cystic ovarian tumors were detected in 250 patients (3.2%). All tumors were < 10 cm in diameter and 89% were <5 cm in diameter. One hundred thirty-five (55%) resolved spontaneously within 60 days, and 115 (45%) persisted. One hundred fourteen of these patients underwent operative tumor removal. Seven patients had ovarian carcinoma, 1 had primary peritoneal cancer, and 1 had metastatic breast cancer to the ovary. Conclusion. Unilocular ovarian cysts <10 cm in diameter in asymptomatic postmenopausal women or women ≤50 years of age are associated with minimal risk for ovarian cancer. In contrast, complex ovarian cysts with wall abnormalities or solid areas are associated with a significant risk for malignancy. These data are important in determining optimal strategies for operative intervention in these patients.