S4033 From Incidental to Alarming: Hematochezia and Constipation Due to a Progressing Colonic Lipoma

Introduction: Colonic lipomas are benign submucosal tumors found in ∼0.2%–4.4% of colonoscopies. Most are <2 cm, asymptomatic, and incidentally discovered. Larger lesions (>2 cm) may cause pain, bleeding, or obstruction, and can mimic malignancy, especially when ulcerated or causing mucosal distortion. Case Description/Methods: In May 2024, a 48-year-old man with a family history of colonic polyps and a personal history of intermittent hematochezia underwent diagnostic colonoscopy. His bleeding episodes were infrequent, self-limited, and without chronic bowel issues or weight loss. Colonoscopy revealed a smooth, 3 cm sessile submucosal lesion in the ascending colon and 2 small polyps—one in the descending colon and one in the sigmoid. Internal hemorrhoids were also visualized. The distal ileal and colonic mucosa appeared normal. Hemorrhoids were presumed the likely cause of his intermittent bleeding. Biopsies confirmed the ascending colonic lesion as a submucosal lipoma—benign adipose tissue without dysplasia or malignancy. Polyp histology was hyperplastic. In October 2024, he was hospitalized with persistent hematochezia. Hemodynamically stable, his labs showed a modest hemoglobin drop suggesting acute blood loss. Contrast-enhanced computed tomography abdomen showed sigmoid wall thickening, pericolonic fat stranding, punctate extraluminal gas, and proximal air-stool levels—raising concern for colitis, ischemia, or a submucosal mass. In March 2025, repeat colonoscopy revealed that the 3 cm lipoma now had central ulceration with contact oozing. No other bleeding source was found. Multiple biopsies were obtained. Histopathology showed focal ulceration and granulation tissue without dysplasia, malignancy, or chronic colitis—consistent with an ulcerated colonic lipoma, now recognized as the bleeding and obstruction source. Although bleeding resolved without transfusion, the ulceration and symptoms prompted referral for endoscopic submucosal dissection. Discussion: Colonic lipomas, found in 0.2%–4.4% of benign colonic tumors, are usually incidental. Lesions >2 cm may cause bleeding, intussusception, or obstruction. Mucosal ulceration can mimic malignancy. Our case highlights the need to reassess lipomas when new symptoms emerge.