Adult Splenic Flexure Colocolic Intussusception Due to a Submucosal Colonic Lipoma Presenting as Acute Abdomen

Adult intussusception is uncommon and usually results from an underlying structural abnormality, particularly in the colon, where malignancy is a major concern. We present a case in which a young woman experienced 4 days of crampy lower abdominal pain, constipation, nausea, vomiting, and inability to pass flatus. Abdominal examination showed tenderness, hyperactive bowel sounds, and no distention; vital signs were stable. Laboratory tests were largely unremarkable, including a white blood cell count of 9.3 × 109/L. Contrast-enhanced computed tomography of the abdomen identified a 9 cm colocolic intussusception at the splenic flexure, led by a 6 cm fat-containing lesion. Follow-up CT showed ongoing intussusception, bowel wall thickening, and a 7.2 × 3.8 cm fat-density lesion, confirming a fixed lead point. After a gastroenterology and surgical consultation, a laparoscopic left hemicolectomy was performed. Intraoperative findings confirmed intussusception, and histopathology revealed a benign submucosal colonic lipoma. This case underscores the rare occurrence of splenic flexure intussusception caused by a large submucosal lipoma, underscoring that persistent intussusception with a risk of malignancy warrants surgical management. Colonic lipoma should be considered in the differential diagnosis of adult colocolic intussusception, especially when malignancy cannot be excluded preoperatively.