Importance: Melanoma treatment has been revolutionized with the development of immune-based therapies that offer durable clinical responses in a subset of patients. Clinical outcomes after treatment by immunotherapy can be influenced by the host's immune system. The immune system is modified with age by age-related immune dysfunction.
Objective: To evaluate if age influences clinical outcome and immune adverse events in patients treated by immunotherapy for metastatic melanoma.
Design, setting, and participants: This was a single-center cohort analysis in patients treated with immunotherapy for metastatic melanoma between January 2007 and February 2016, in the Lyon Sud Hospital, France. A total of 92 patients with metastatic melanoma treated with ipilimumab, nivolumab, or pembrolizumab were retrospectively analyzed.
Main outcomes and measures: Overall survival, progression-free survival, and immune-related adverse events were evaluated for each treatment line according to the patients' age.
Results: A total of 92 patients were eligible and included in this study for a total of 120 lines of treatment. Fifty-four patients were included in the cohort that was 65 years or younger (24 [44%] were female; mean [SD] age, 48.1 [12.5] years), and 38 patients were included in the cohort that was older than 65 years (12 [34%] were female; mean [SD] age, 74.8 [6.9] years). Mean follow-up duration starting at treatment initiation was 12.5 months. Patients older than 65 years treated with immunotherapy had a better mean progression-free survival (4.8 vs 3.4 months; P = .04) and overall survival (not reached vs 10.1 months; P = .009) than younger patients in univariate analysis, and after adjusting on prognosis covariates. This was particularly true with patients treated with anti-programmed cell death protein 1. Common immune-related adverse effects were similar in both cohorts.
Conclusions and relevance: Age might be associated with a better clinical outcome after treatment with immunotherapy in the real-life setting. In our cohort, older patients did not have more immune-related adverse events. Further studies are warranted to confirm our results and describe the underlying mechanisms involved.