A case report of carcinosarcoma of gall bladder characterized by good response to the chemotherapy

Carcinosarcoma, which comprises less than one percent of all gall bladder neoplasms, is characterized by the presence of variable proportions of carcinomatous and sarcomatous elements. We report a case of gall bladder carcinosarcoma arising in 69-year-old female. The patient was admitted to our hospital because of epigastric pain. CT revealed gall bladder tumor and liver invasion, portal vein invasion and peritoneal dissemination of the tumor. At the time of diagnosis, the tumor was considered inoperable. Following diagnosis, the patient received chemotherapy (1 course of gemcitabine). It was effective, and the tumor became operable. Curative surgical resection was performed. Histologically, viable tumor component remained mainly in the gall bladder. The tumor component consisted of sarcomatous and carcinomatous elements, and the latter was composed of squamous cell carcinoma and adenocarcinoma. In addition, remarkable necrosis and fibrosis was seen inside the tumor, especially in the part of liver invasion. We thought that the necrotic and fibrotic change indicated antitumor activity of the chemotherapy. On the basis of these findings, the tumor was diagnosed as carcinosarcoma of gall bladder. In summary, we reported the rare case of carcinosarcoma arose in gall bladder, which showed good response to the chemotherapy.