Duodenocolic fistula after laparoscopic ileocecal resection for ascending colon cancer: A case report.

Introduction: Duodenoileal and duodenocolic fistulas are rare complications often associated with inflammatory bowel disease, cancer, or peptic ulcers. Fistulas that form between the duodenum and a gastrointestinal anastomosis site following colorectal cancer surgery are extremely rare. Here, we report a rare case of duodenocolic fistula following laparoscopic ileocecal resection for ascending colon cancer. Case presentation: A 70-year-old man, who underwent laparoscopic ileocecal resection for ascending colon cancer, exhibited no intraoperative injury to the duodenum. On postoperative day (POD) 31, the patient presented with fatigue and increased inflammatory markers. Computed tomography and upper gastrointestinal endoscopy revealed a fistula between the duodenum and the ileocolic anastomosis. Conservative management, including bowel rest, parenteral nutrition, antibiotics, and proton pump inhibitors, resulted in the complete closure of the fistula by POD 70, and the patient was discharged on POD 73. Discussion: To our knowledge, this is only the second reported case of duodenoileal or duodenocolic fistulas following right-sided colon cancer surgery, and the first to occur during the early postoperative period. We hypothesize that subclinical anastomotic leakage, chronic inflammation, and mechanical contact from the surgical stapler may have contributed to fistula formation. Its small size and early detection likely facilitated the successful conservative outcome. Conclusion: Although exceedingly rare, duodenocolic fistula may occur following right-sided colectomy. Early identification and appropriate conservative management may result in a favorable outcome without the need for invasive surgical intervention.