Challenges of laparoscopic resection of a giant rectosigmoid lipoma: a case report with a mini-review

Introduction and importance: Giant colonic lipomas are rare benign tumors that can closely mimic colorectal malignancies when they become large or symptomatic. Their nonspecific presentation and variable imaging appearances often complicate diagnosis, particularly in older adults. Advanced imaging modalities, such as computed tomography (CT) and magnetic resonance imaging (MRI), improve characterization, yet surgical confirmation is frequently required. This report describes a case of a giant rectosigmoid lipoma, emphasizing the diagnostic difficulties and clinical relevance of this rare entity. Case presentation: A 70-year-old male presented with a 2-month history of intermittent constipation and diffuse, cramp-like abdominal pain. Physical examination and laboratory investigations were unremarkable. CT revealed a well-circumscribed rectosigmoid mass, and MRI confirmed a giant lipoma with classic fat-signal characteristics and no signs of invasion. Clinical discussion: Giant lipomas exceeding 5 cm in size are more likely to become symptomatic and may imitate malignant lesions on endoscopy and imaging. The patient’s mild, nonspecific symptoms reflect patterns described in the literature, where luminal distensibility in certain colonic segments delays obstructive features. MRI provided diagnostic clarity in this case, contrasting with reports in which atypical features necessitated exploratory surgery. Laparoscopic segmental resection remains the recommended treatment for symptomatic, large, or diagnostically uncertain lipomas. Conclusion: Giant rectosigmoid lipomas, though uncommon, should be considered in the differential diagnosis of colorectal masses. MRI can facilitate a confident preoperative diagnosis, and timely surgical resection offers excellent outcomes when performed electively.