A low grade malignant neoplasm characterized by the presence of a benign epithelial component (tubular and cleft-like glands) and a low grade sarcomatous component that contains varying amounts of fibrous and smooth muscle tissues. In a minority of cases, the sarcomatous component contains heterologous elements including striated muscle, cartilage, and fat. It occurs in the uterine corpus, ovary, fallopian tube, cervix, and vagina. It may recur and in a minority of cases may metastasize to distant anatomic sites.