"Unusual Manifestation of Ectopic Human Chorionic Gonadotropin-Producing Cancers"

Abstract

Gynecomastia results from 1) Increased level of circulating estrogen, in particular estradiol, 2) Increased breast sensitivity to circulating estrogen, or 3) An altered balance of estrogen (stimulatory effect) and androgen (inhibitory effect).Estrogen stimulates ductal epithelial hyperplasia, ductal branching and elongation, proliferation of the periductal stroma, and vascular distribution in the breast [5,6].