An Unusual Case of Three Synchronous Primary Gastrointestinal Carcinomas

Abstract

FigureA 57 year old man presented with complaint of on and off vomiting and 20 lb weight loss within 8 months. He was treated for prostate cancer with radiation therapy about a year ago. Family history was significant for prostate cancer in his uncle and uterine cancer in his sister in their fifties. Lab studies showed iron deficiency anemia and positive fecal occult blood test. Esophagogastroduodenoscopy was unremarkable. Colonoscopy revealed a large fungating mass in the ascending colon and biopsy showed moderately differentiated adenocarcinoma. A right hemicolectomy was performed which showed two separate tumors in the ascending colon measuring 3 cm and 6.5 cm respectively, separated by 1.5 cm of normal mucosa. The postoperative course was complicated by obstipation and increased amount of nasogastric tube drainage. Computed tomography of abdomen and pelvis showed markedly distended stomach and duodenum and abrupt transition point in the proximal small bowel with no contrast beyond that level. Exploratory laparotomy showed an obstructing mass in the 3rd portion of the duodenum for which duodenectomy with primary duodenojuejunostomy was performed. Pathological examination revealed a 3.5 cm circumferential obstructing adenocarcinoma of the duodenum. Tumor tissue was tested high for microsatellite instability and genetic testing showed homozygous MSH 2 mutation. Small intestinal carcinomas are among the rarest types of cancer accounting for only 2% of gastrointestinal carcinomas. Though it is included in the tumor spectrum of Hereditary Non-Polyposis Colorectal Cancer, its incidence in those patients is rare. To the best of our knowledge, this is the first case report of three synchronous primary gastrointestinal carcinomas. [figure1][figure2]Figure