Duodenocolic fistula diagnosed by endoscopy: a rare complication of colon cancer

Duodenocolic fistula (DCF) is a rare complication of colon cancer with only 70 cases reported since its first description in 1862. Owing to its rarity, current knowledge on DCF still relies on single case reports. We present 2 cases of DCF from a hepatic flexure adenocarcinoma demonstrated initially by endoscopy. 2 adult male patients were admitted due to a 2-3-month history of right-upper quadrant pain, vomiting, diarrhoea and a palpable right upper quadrant mass. In both cases, a circumferential, friable mass was noted on upper endoscopy at the second portion of the duodenum, leading to the ascending colon. A similar-looking lesion was also noted on colonoscopy. Biopsies in both cases confirmed colonic adenocarcinoma. Owing to the advanced nature of the disease, en bloc resection was not achieved. Instead, tube jejunostomy and loop ileostomy were created. Both patients were discharged tolerating feeding with improvement in symptoms.