Postmenopausal uterine bleeding due to estrogen production by gonadotropin-secreting lung tumors

Two postmenopausal women are described who had uterine bleeding due to hormone production by lung tumors--a large cell carcinoma in one case and a choriocarcinoma in the other. Both tumors stained positively for one or more placental peptides (human chorionic gonadotropin [hCG], placental lactogen, or pregnancy-specific beta-1 glycoprotein) and both patients had extremely elevated serum levels of hCG, suggesting the tumors had some placental-like endocrine function. Clinical and hormonal data supported the concept that the uterine bleeding resulted from estrogen excess due to steroid bio-transformation by the tumors.