Association of immune-checkpoint inhibitors and the risk of immune-related colitis among elderly patients with advanced melanoma: real-world evidence from the SEER-Medicare database.

Risk of colitis (inflammation of the large intestine) in elderly patients with melanoma treated with immune-checkpoint inhibitors (a group of medications that uses the patient's immune system to fight cancer) While the anti-cancer agents known as immune-checkpoint inhibitors have had a great impact on the treatment of melanoma, they may also have side effects. This study estimated the risk of colitis, a chronic inflammation of the colon, in elderly patients with melanoma treated with anti-cytotoxic T-lymphocyte antigen 4 (anti-CTLA4) or anti-programmed cell-death 1 (anti-PD1) agents, using data from the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database. Overall, we found that the risk of colitis was not different between anti-PD1 users and anti-CTLA4 users with advanced-stage melanoma. However, after including patients across all stages of melanoma, we found a significantly lower risk of colitis with anti-PD1 compared with anti-CTLA4.