Steroid excretion patterns in postmenopausal women with benign and neoplastic endometrium

The climacteric ovary as a functional gonadotropin-driven androgen-producing gland

OBJECTIVE

To assess the hypothesis that the climacteric ovary is a functional endocrine gland.

DESIGN

Review of the English-speaking literature as it relates to the physiology and pathophysiology of the climacteric ovary.

RESULTS

By several accounts, the climacteric ovary appears to be a gonadotropin-dependent androgen-producing gland. Although the estrogen-producing potential of the climacteric ovary remains a matter of controversy, most studies would suggest limited aromatase activity.

CONCLUSIONS

[1] The climacteric ovary is not a defunct endocrine organ. [2] The climacteric ovary is a site of gonadotropin reception and action. [3] The climacteric ovary contributes few if any estrogens to the circulating pool by way of direct production. [4] Circulating estrogens are derived virtually exclusively from the extraglandular conversion of androgens, a proportion of which are of ovarian origin. [5] The climacteric ovary contributes 40% and 20% of the total production rates of T and androstenedione, respectively. [6] Androgen biosynthesis by the climacteric ovary is partially gonadotropin-dependent.

Role of estrogens and progesterone in the etiology and prevention of endometrial cancer: review

Our present knowledge of the role of sex steroids in the development as well as the prevention of endometrial cancer is reviewed. Factors which increase the exposure of the uterus to unopposed estrogens, either exogenous or endogenous, are associated with increased risk of endometrial adenocarcinoma. However, there is increasing evidence that progestogens can reverse endometrial hyperplasia and protect against the development of endometrial cancer. The mechanisms to explain the antiestrogenic effects of progestogens include changes in enzyme activity and steroid receptors in endometrial tissue. Postmenopausal women treated with combined estrogen and progestogen have the lowest incidence of endometrial carcinoma. Oral contraceptives containing both estrogen and progestogen in each tablet are protective against adenocarcinoma of the endometrium, while the sequential oral contraceptive pills afforded less protection. The risks and benefits of these hormone therapies are discussed in relation to the etiology and prevention of endometrial cancer.

Testosterone metabolism in endometrial cancer

Plasma testosterone (PCT), metabolic clearance (MCRT), and production rates (PRT) of testosterone and conversion ratio of testosterone to androstenedione (CRppTA) were performed on 11 patients with endometrial cancer and on a control group of five postmenopausal women. The PCT, MCRT, and PRT of patients with endometrial cancer are in the normal postmenopausal range. The conversion of testosterone to androstenedione in patients with endometrial cancer was significantly decreased.