A Rare Case of Gastric Carcinosarcoma with Neuroendocrine Differentiation

ABSTRACT

Carcinosarcoma of the stomach is a rare biphasic tumor that consists of both carcinomatous and sarcomatous components. In the gastrointestinal tract, carcinosarcoma is most frequently seen in the esophagus and rarely in the stomach. Tubular or papillary adenocarcinomas are common carcinomatous components, whereas mesenchymal sarcomatous components may vary. Neuroendocrine carcinomatous differentiation in carcinomatous components is extremely rare. We report a 62-year-old female patient with a history of dyspepsia for one-month-history. Endoscopic findings showed a ulcerofungating lesion, which infiltrated from the posterior wall of the antrum to the posterior wall of the gastric angle. Radical subtotal gastrectomy was performed. In the resected specimen, immunohistochemical studies showed two positive reactions for epithelial and mesenchymal markers. Based on the above findings, the patient was diagnosed with a gastric carcinosarcoma with neuroendocrine differentiation.