A 30-year-old man comes to the physician for a 2-month history of swelling of both breasts. He has been receiving levothyroxine and prednisone since undergoing removal of a pituitary adenoma one year ago. He began receiving human chorionic gonadotropin (hCG) injections 3 months ago. As a result of these hCG injections, which of the following is the best explanation for gynecomastia in this patient?
Adrenal cortex secreting 17-hydroxypregnenolone
Breast tissue direct stimulation by hCG
Liver failing to metabolize estrogen
Pituitary gland re-secreting prolactin
Testes secreting estrogen
