Malignant mixed Müllerian tumor of the endometrium in a young woman with polycystic ovaries.

A 19-year-old female with Stein-Leventhal syndrome and polycystic ovaries was found to have a malignant mixed Müllerian tumor (MMMT) of the uterus with superficial myometrial invasion. This patient is the youngest reported with MMMT of the endometrium. The association of endometrial malignancies and polycystic ovaries is reviewed. The tumor was found to have above normal levels of estradiol and progesterone receptors. A possible role of estrogen stimulation in the genesis of some MMMTs is suggested.