So-called carcinosarcoma of the gallbladder; spindle cell carcinoma of the gallbladder: report of a case.

We report a so-called carcinosarcoma of the gallbladder in a 53-year-old man. The findings of ultrasonography, computed tomography, endoscopic retrograde cholangiopancreatography, and angiography revealed a large mass of the gallbladder with a cholesterol stone. He underwent three operations, and died from liver failure with multiple liver metastasis immediately after the third operation. A pathological examination revealed neoplastic tissue composed of sarcomatous and glandular components. Hematoxylin-eosin stain proved the presence of carcinosarcoma in the gallbladder, but an immunohistochemical study proved that the sarcomatous component was stained by antivimentin and also anticytokeratin antibodies, which thus proved it to be so-called carcinosarcoma of the gallbladder. As a result, an immunohistochemical study is considered to provide valuable information regarding the identification of sarcomatous elements in such cases.