Postmenopausal ovarian follicle cyst: An unusual cause of estrogen excess

Six years after menopause, a 61-year-old woman complained of enlarging, tender breasts. The serum follicle-stimulating hormone level was 62 mIU/ml; the serum estradiol value was 91 pg/ml; and challenge with progesterone, 100 mg i.m., induced withdrawal bleeding. Histologic examination of a hysterectomy with bilateral salpingo-oophorectomy specimen showed proliferative endometrium and an involuting, luteinized follicle cyst of the left ovary. A follicle cyst causing symptomatic hyperestrogenism after a menopause documented by biochemical tests has not been previously reported.