Carcinosarcoma of the uterus: MR findings

PURPOSE: To clarify the imaging characteristics of carcinosarcomas, which are the most common malignant mixed epithelial and mesenchymal tumors (MEMTs) of the uterus. MATERIALS AND METHODS: We retrospectively reviewed MR findings of 17 histopathologically confirmed cases with carcinosarcomas, including the size, growth pattern, signal intensity, contrast enhancement, and extrauterine spread in each case. RESULTS: The maximum tumor diameter was 11-165 mm (mean 88 mm). Nine cases (53%) showed exophytic with a stalk and eight cases (47%) showed broad-based exophytic growth. None of them showed invasive growth. Fourteen cases (82%) were isointense and three cases (18%) were hyperintense to myometrium on T1-weighted images (T1WI). An extremely high intensity area suggesting intratumoral hemorrhage was seen in only two cases. In 15 cases (88%), more than half of the tumor showed higher signal intensity than the outer myometrium on T2WI. Eight of the 16 cases (50%) had an unenhanced area, whereas 13 cases (81%) had a strongly enhanced area. Extrauterine extension was observed in only two cases (12%) at initial presentation. CONCLUSION: Uterine carcinosarcomas reveal a spectrum of imaging findings with a high signal on T2WI, with a prolonged intense enhancement being the most common imaging feature.