Efficacy of adjuvant immune checkpoint inhibitors in melanoma patients ≥75 years – results of a real-world cohort including 456 patients

Abstract Background Immune checkpoint inhibitors (ICI) applied in patients with melanoma in an adjuvant setting have proved safety and efficacy in several studies, but data on elderly patients aged 75 years or more is scarce. Aim of this study was to investigate efficacy and safety of adjuvant ICI in patients aged ≥ 75 years compared to patients < 75 years in a real-world setting. Methods We retrospectively analyzed clinical data, including occurrence of immune-related adverse events (irAE) and outcome of 456 patients that had been treated with adjuvant ICI between January 1, 2018 and December 20, 2022. We then compared patients aged ≥ 75 years (n=117) to patients < 75 years (n=339) in terms of safety and progression-free survival (PFS). Results and conclusion ICI was well tolerated in both groups, with no significant difference observed in the overall occurrence of irAEs. However, within the elderly subgroup there was a significant higher proportion of skin or nephrological toxicity and colitis/diarrhea compared to the other group. In terms of efficacy there was a significant shorter progression-free survival in patients aged ≥ 75 years. Adjuvant ICI in patients ≥ 75 years was less effective and furthermore associated with an increased risk for skin, renal or bowel toxicity. Therefore, in elderly patients, adjuvant ICI should be used with precaution.