Non-Sex Cord-Stromal Ovarian Tumors Frequently Produce and Secrete Estrogen in Postmenopausal Women: Impact on Bone Metabolism and Abnormal Endometrial Histology

Abstract

We investigated whether the estrogen released from non-sex cord-stromal ovarian tumors has biological effects on bone and endometrial tissue in postmenopausal women. A total of 132 patients with malignant (n = 112) or benign (n = 20) gynecological disease with normal postmenopausal ovaries were recruited as a control group (group C). The 75 patients with ovarian tumors were divided into 2 groups: group L (serum estradiol [E2] level of < 20 pg/ml; n = 42) and group H (serum E2 level of > 20 pg/ml; n = 33). The subjects' serum E2 levels, bone mineral density, urinary levels of the N-telopeptide of type I collagen, and serum levels of bone-specific alkaline phosphatase were measured before and after surgery. Histological examinations of the endometrium were carried out in the 75 patients with non-sex cord-stromal ovarian tumors. High serum E2 levels were detected in 33 (44%) of 75 patients with ovarian tumors. The serum E2 levels of group H were significantly decreased after surgery. In the other subjects, there were no significant differences between the serum E2 levels observed before and after surgery. The mean preoperative N-telopeptide of type I collagen and bone-specific alkaline phosphatase levels of group H were significantly lower than those of group C. The bone mineral density values of groups L and H were significantly decreased after surgery. Five (6.7%) of 75 patients with non-sex cord-stromal ovarian tumors displayed abnormal endometrial histology, including 4 patients with grade 1 endometrioid cancer. The E2 released from ovarian tumors might have biological effects on bone metabolism and the incidence of abnormal endometrial histology.