Effect of natural "micronized" progesterone on the chorionic gonadotropin concentrations in cyst fluids of women with gross cystic breast disease.

Gross cystic breast disease (GCBD) is common in women, especially in the age range between 35 and the menopausal years. The present study examined the possible role of progesterone (Pg) in the chorionic gonadotropin (hCG) concentration in GCBD. The breast cyst fluids (BCFs) were drawn by fine needle aspiration between the sixth and the eighth day of the menstrual cycle and twenty days later. On the day of the first aspiration the patient began to take 100 mg of natural micronized Pg orally until the second aspiration. At both times blood samples were also taken. Determinations were done of both BCFs and blood sample using two fully automated chemiluminiscent enzyme immunometric assays. Pg has been demonstrated to induce a significant increment in hCG + free ss-hCG (median, range): 0.27 ng/ml, 0.12-6.24 vs. 1.92 ng/ml, 0.12-423.5; free ss-hCG: 0.11 ng/ml, 0.02-2.40 vs. 0.91 ng/ml, 0.02-58.40 in the BCFs, with no change in the circulating concentrations of the hormone. None of the sera studied presented levels of hCG + free ss-hCG or free ss-hCG above 0.5 ng/ml or 0.1 ng/ml, respectively. The occurrence of hCG or a derivative polypeptide in BCFs, when they are present in high concentrations suggests that this glycoprotein could be synthesized in situ and possibly involved in the pathogenesis of GCBD by the degree of differentiation of breast epithelial cells induced by the hormone.