Histology Tumors contain adenocarcinoma admixed with one or more malignant stromal elements, which may be endometrial stroma, smooth muscle, skeletal muscle, bone, cartilage or fat. Note malignant glands and stroma. The prognosis is poor. The tumors often present at an advanced stage. Occult metastases may be present even in those with stage I or II disease.
Strongest factor correlating with a poor outcome is deep myometrial invasion.
Invasion to the middle or outer third of myometrium is invariably associated with microscopic lymphatic and vascular channel invasion, therefore lymph node and hematogenous spread to lung and liver are common. The presence of heterologous elements appears to have no effect on prognosis but the type of adenocarcinoma present influences the prognosis. Metastases usually consist of the adenocarcinomatous element. There are virtually no long-term survivors among those whose tumors have extended beyond the uterus at time of diagnosis. Infections Benign Cond.