Abstract

Carcinosarcoma, often referred to as "malignant mixed tumor" is a rare neoplasm, but this tumor occurs in various organs, including the gallbladder. We report herein a carcinosarcoma of the gallbladder which consisted of adenocarcinomatous and undifferentiated sarcomatous ares, the latter differentiating towards abundant osteoid and calcified but nonlamellated bony trabeculae formation. There are 18 reported cases of this type tumor of the gallbladder in the literature.