1569 Duodenocolic Fistula Presenting as Feculent Emesis: An Unfortunate Case of Aggressive Colon Adenocarcinoma in a Young Patient

Abstract

INTRODUCTION: Duodenocolic fistula is am extremely rare complication of colon adenocarcinoma. Patient typically present with nausea, vomiting and abdominal pain. Rarely patients can present with feculent emesis in which case diagnosis can be confirmed with imaging and endoscopic evaluation. We present an unfortunate case of duodenocolic fistula in a young patient. CASE DESCRIPTION/METHODS: 34 yo Hispanic male presented to the Emergency room with complains of weight loss, early satiety and vomiting of brownish fluid for the past 3 days. Patient has a previous history of Cecal adenocarcinoma diagnosed at age 32 and underwent right hemicolectomy. Patient was lost to follow up and failed to follow up with oncology. Lately patient had been experiencing early satiety and family members had been complaining of halitosis. He later developed nausea and vomiting of brown color fluid concerning for fecal matter. He denied any abdominal pain and continued to have regular bowel movements. Clinical exam was significant for extreme halitosis although no signs of bowel obstruction. Initial workup was positive for microcytic anemia. CT abdomen revealed 5.1 × 4.8 cm thick walled circumscribed fluid collection contiguous with the descending portion of the duodenum communicating with the adjacent colon near the hepatic flexure (Figure 1). Upper Endoscopic examination revealed a large ulcerated fistulous connection between the duodenal bulb and the colon along with large amount of fecal matter pouring into the stomach through the fistulous connection (Figures 2 and 3). Ulcer edge biopsy confirmed recurrence of colon adenocarcinoma. Patient subsequently underwent whipple's procedure with resection of the previous ileocolic anastomosis and creation of a new ileocolic anastomosis. Testing for DNA mismatch repair gene by immunohistochemistry revealed loss of MSH2 & MSH6 suggestive of microsatellite instability consistent with Lynch Syndrome. Patient and family were subsequently referred for genetic counselling. DISCUSSION: Duodenocolic fistula is a rare presentation of colon cancer. There have been only a few case reports of colon cancer presenting as Duodenocolic fistula. Diagnosis requires a high degree of suspicion especially in patients presenting with feculent emesis, which can be confirmed with imaging and endoscopic evaluation. Successful surgical management with fistulectomy along with Whipple's procedure has shown good outcomes.