Carcinosarcoma of Gallbladder with Osteosarcomatous Differentiation - a Case Report with Review of Literature.

A 44-year-old female presented with dull upper abdominal pain. Contrast-enhanced computed tomography (CECT) of the abdomen revealed a well-distended gallbladder with multiple foci of minimally enhancing, intraluminal, soft tissue lesion, and hyperdensity on non-contrast scan measuring 4.3 × 3.5 cm in the fundus with few calculi embedded in it. There was no evidence of extraluminal extension. The patient underwent extended cholecystectomy with liver wedge resection. Histologically, the tumor showed both carcinomatous and sarcomatous components, with prominent osteosarcomatous differentiation. We report this unusual case and present a review of all cases of carcinosarcoma of the gallbladder with sarcomatous differentiation. Despite curative resection, CSGB prognosis remains poor, and thus, the authors recommend to focus their efforts to improve the surgical outcomes.