Colonic lipomas are rare benign tumors that may appear throughout the entirety of the gastrointestinal tract, with a predisposition to appear in the colon. Patients with colonic lipoma are typically asymptomatic, making their diagnosis rare and incidental. This case report intends to investigate and clarify the decision-making process regarding surgical segmental colonic resection versus local excision via the study of a 48-year-old man with ulcerative colitis diagnosed in 2006, undergoing treatment with infliximab and without exacerbations since 2010. The patient presents with anal prolapse and colonic obstruction due to intussusception. After performing a CT scan with contrast, an intramural lipoma in the sigmoid colon measuring 5.5×4.7×4.6 cm was revealed. An elective oncologic sigmoid resection was the treatment of choice with regard to its size, location, and associated symptoms, especially when presenting complications like intussusception. Such a decision allowed for an improvement in pain control, shorter hospitalization, and faster recovery. The decision was also taken considering the safety risks regarding the size of the lesion and the presence of the intussusception.