Right colon cancer presenting as hemorrhagic shock.

A 67-year-old man visited our hospital with a history of continuous hematochezia leading to hemorrhagic shock. An abdominal computed tomography scan revealed a large mass in the ascending colon invading the duodenum and pancreatic head as well as extravasation of blood from the gastroduodenal artery (GDA) into the colon. Colonoscopy revealed an irregular ulcerative lesion and stenosis in the ascending colon. Therefore, right hemicolectomy combined with pylorus-preserving pancreaticoduodenectomy was performed. Histologically, the tumor was classified as a moderately differentiated adenocarcinoma. Moreover, cancer cells were mainly located in the colon but had also invaded the duodenum and pancreas and involved the GDA. Immunohistochemically, the tumor cells were positive for cytokeratin (CK)20 and carcinoembryonic antigen (CEA) but not for CK7 and carbohydrate antigen (CA)19-9. The patient died 23 d after the surgery because he had another episode of arterial bleeding from the anastomosis site. Although En bloc resection of the tumor with pancreaticoduodenectomy and colectomy performed for locally advanced colon cancer can ensure long-term survival, patients undergoing these procedures should be carefully monitored, particularly when the tumor involves the main artery.