Malignant mixed mullerian tumor arising in extragenital endometriosis: report of a case and review of the literature.

A primary malignant mixed Mullerian tumor (MMMT) was found in the wall of the rectum of a 67-year-old female. The uterus, fallopian tubes, and ovaries had been previously excised for benign disease. The tumor was associated with foci of benign endometriosis. A literature review of extragenital MMMTs indicates that these are extremely rare tumors. This case supports the theory that endometriosis may serve as a progenitor to extraendometrial malignancy.