CT features of primary hepatic carcinosarcoma

Objective Purpose We studied the CT features of primary liver carcinosarcoma in order to raise the awareness of it. Methods Clinical and CT data of 7 cases of liver carcinosarcoma proved by operation and pathology were collected, and retrospectively analyzed. Results A total of 7 patients were included in this study from January 2009 to February 2018, 6 of whom were male and 1 female. The patient's age range was 42-64. All patients were treated with abdominal pain as the main clinical symptom. Three patients had a history of cirrhosis. Four patients had a history of chronic hepatitis B. CA199 and AFP were positive in 3 patients and CA125 positive in one patient. The inner diameter of the tumor was 7.0-27.0 cm. Four cases of showed pseudocapsular formation of fibrous tissue around the tumor. Tumor tissues in 7 cases were composed of carcinomatous components and sarcomatous components. The carcinomatous components included 5 cases of hepatocellular carcinoma and 2 cases of cholangiocarcinoma. The components of sarcoma included fibrosarcoma in 4 cases, angiosarcoma in 2 cases and malignant fibrous histiocytoma in 1 case. All 7 patients underwent plain CT scan and three phase contrast enhanced scan. All 7 cases of tumor were single lesions with huge volume. Of them, 3 cases had protruding hepatic contour and 4 cases had tumor localized in the contour of liver. Three cases of tumors were round, four cases of tumors were irregular. On plain CT scan, the tumor showed inhomogeneous and low density. Large flake or thick-walled septal multilocular cystic areas can be seen in the lesion. In contrast, enhanced CT scan, the lesions showed gradual enhancement of the edge to the center on the three phase of contrast enhanced imaging. At arterial stage, the tumor's parenchyma presented as mild and moderate enhancement. In portal and delayed phase, the density of tumor parenchyma was slightly lower in 4 cases and equal in 3 cases. Conclusion Primary liver carcinosarcoma is a rare malignant tumor in clinic. These CT signs such as large mass from the liver, large flake or thick-walled septal multilocular cystic areas, on the three phase enhanced images, the lesion were gradually filled and enhanced from edge to the center, at portal vein phase and delayed stages, the tumor's parenchyma showed slightly lower densities, and so on, which will contribute to the diagnosis of liver carcinosarcoma.