Two Patients with Large Colonic Lipomas for which Endoscopic Unroofing was Ineffective

Endoscopic unroofing is effective for treating large colonic lipomas. However, additional endoscopic resection is occasionally required when the outcomes of initial unroofing are incomplete. The colonoscopy of an 82-year-old woman with abdominal pain revealed a yellowish lipoma of about 20 mm in the transverse colon. The mass was treated by unroofing, but a follow-up colonoscopy 5 days later revealed residual lipoma. One month later, the regenerated surface had become covered with mucosa, and the status of the lipoma had returned to that before unroofing. The colonoscopy of a 74-year-old man with abdominal pain and melena revealed a 50-mm-wide protruding lipoma in the transverse colon. The mucosa of the upper third of the lipoma was excised using an electric knife and snare, which allowed the immediate partial drainage of adipose tissue. Unroofing proceeded, but 7 days later, the unroofed surface had become coated with a white substance, and the residual lipoma required additional endoscopic resection. Colonic lipomas are often asymptomatic. However, patients with abdominal pain and hemorrhage should be treated in consideration of complete resection, but not by unroofing, which could leave a residual tumor. Drainage should be confirmed after unroofing and any residual lipoma should be treated by additional resection.