Giant Sigmoid Lipoma With Necrosis Mimicking Colorectal Cancer and Intussusception: A Case Report

We describe a case of a giant sigmoid colon lipoma with clinical and radiological features mimicking colorectal carcinoma, highlighting the diagnostic and therapeutic challenges associated with large submucosal colonic lesions. The patient presented with symptoms of bowel obstruction and cross-sectional imaging findings that highly suggested malignancy. The patient's clinical presentation, imaging studies, colonoscopic findings, and histopathological results were reviewed. The patient underwent colonoscopic evaluation, which revealed a bulky, ulcerated lesion, further increasing suspicion for malignancy; due to the size of the lesion and inability to exclude cancer preoperatively, a laparoscopic segmental colectomy was performed. Histopathology examination confirmed a giant submucosal lipoma with compression-related necrosis and associated chronic colitis. Postoperative recovery was uneventful. This case emphasizes the value of correlating and integrating clinical, endoscopic, and imaging findings when evaluating large colonic lesions. Recognition of giant colonic lipomas as a potential mimic of colorectal carcinoma is essential to guide appropriate management and may help avoid unnecessary extensive surgical intervention.