Role of immunohistochemical analysis in the diagnosis of gastric carcinosarcoma, a rare tumour - case report

Carcinosarcoma is a malignant tumour that has carcinomatous and sarcomatous components occurring rarely in the stomach with only a handful of case reports, mainly from Japan. We report a case of carcinosarcoma in a fifty-two-year-old female with clinical and histopathological features. The patient underwent complete workup followed by surgical resection. Macroscopically, the tumour was large and ulcerating. Microscopically, it was a carcinosarcoma with myogenic differentiation. Immunohistochemical analysis was done, which led to the diagnosis of gastric carcinosarcoma. Carcinosarcoma can mimic an adenocarcinoma clinically, and making a diagnosis on the basis of endoscopy or radiology alone is not possible. Our case report highlights the importance of immunohistochemical analysis in the diagnosis of gastric carcinosarcoma.