Adult duodenal intussusception with horizontal adenoma: A rare case report

BACKGROUND: Adult duodenal intussusception rarely occurs, and the majority of duodenal adenomas are located in the descending part of the duodenum. Therefore, adenomas in the horizontal part of the duodenum presenting as duodenal intussusception in adults are extremely rare. CASE SUMMARY: A 36-year-old man complained of abdominal pain for 13 d. Blood analysis showed anemia. Magnetic resonance cholangiopancreatography and computed tomography revealed a tumor in the horizontal part of the duodenum as the main finding, leading to duodeno-duodenal intussusception. No obvious abnormalities were found on endoscopy or upper gastrointestinal radiography. He was diagnosed with duodenal intussusception secondary to duodenal adenoma. Laparotomy showed duodeno-duodenal intussusception and a tumor in the horizontal part of the duodenum near the ascending part. Postoperative pathology revealed tubular-villous adenoma with low-grade glandular intraepithelial neoplasia (local high-grade intraepithelial neoplasia). He was discharged without complications. CONCLUSION: This case highlights that rational use of computed tomography, magnetic resonance cholangiopancreatography, endoscopy and upper gastrointestinal radiography for preoperative diagnosis and timely surgery is an effective strategy for the treatment of adult duodenal intussusception with duodenal masses.