Flexible Sigmoidoscopy Rather than Colonoscopy Is Adequate for the Diagnosis of Ipilimumab-Associated Colitis.

Objectives: Treatment with ipilimumab, a cytotoxic T lymphocyte antigen-4 approved for metastatic melanoma can result in clinically significant immune-mediated drug injury in the form of colitis. Timely diagnosis and response are essential for optimal management. The aims of our study were to determine the percentage of our patients with ipilimumab-associated colitis in which the colitis could be diagnosed by flexible sigmoidoscopy only and to describe the variations in endoscopic and histologic findings as well as the patients' clinical courses.