Type of Preparation: Conventional Magnification: High Clinical History: 68 year old woman with postmenopausal bleeding and an enlarged uterus on pelvic exam Interpretation: Other Malignant Neoplasms: MMMT (carcinosarcoma) Cytomorphologic Criteria: These spindle cells with round or oval pleomorphic nuclei, slightly irregular nuclear membranes, and multiple prominent nucleoli constitute the sarcomatoid component of this tumor. These cells are admixed with the more obvious epithelial component of the tumor (left upper corner). The bloody background and tumor diathesis are also represented in this picture. Explanatory Notes: Sarcomatoid elements are usually spindle cells. they may appear stromal, fibroblastic or leiomyosarcomatous. Occasional heterologous elements may include rhabdomyosarcoma, chondrosarcoma or osteosarcoma. In a poorly differentiated tumor a separate sarcomatous and epithelial component may be difficult to identify. A uterine sarcoma should be considered in the differential diagnosis. (combine as split screen with Misc-c-st8). Follow-up: MMMT of endometrium (hysterectomy)