Treatment of endometrial hyperplasia with cyproterone acetate histological and hormonal aspects.

A regime of cyproterone acetate (CPA) (300 mg/day by the oral route for 30 days) has been used in 10 post-menopausal women with endometrial hyperplasia (8 atypical and 2 adenomatous). Androstenedione (A), estrone (E1), testosterone (T) and estradiol (E2) plasma levels were determined before and at the end of treatment. The regression of endometrial hyperplasia was ascertained histologically in all patients after 30 days of therapy. All steroids showed a significant decrease (p less than 0.05) as compared with their corresponding basal values. Moreover, the E1/A ratio was significantly lowered (p less than 0.01) following CPA administration (5.9 + 2.9% to 2.5 + 0.6%). From these data it is evident that CPA can not only act as a progestin, but may also reduce the endogenous estrogen production, lowering either the adrenal production of A (the most important estrogen precursor in the post-menopause) or the A to E1 peripheral conversion.