Body mass index and type 2 diabetes mellitus as metabolic determinants of immune checkpoint inhibitors response in melanoma

BackgroundImmune checkpoint inhibitors (ICIs) have improved survival outcomes in melanoma. Studies exploring the correlations between body mass index (BMI), type 2 diabetes (T2DM) and the outcomes of ICI treatment have yielded inconsistent results. In this study, we aim to investigate the effects of BMI and T2DM on survival outcomes of patients with melanoma receiving ICIs.MethodsA retrospective multicenter cohort of patients with melanoma treated with ICIs was analyzed. Overall survival was evaluated with Kaplan-Meier survival analysis, univariate Cox and multivariate Cox proportional hazards model. Propensity-score matching (1:1) analysis between overweight and non-overweight groups was done and survival analyses and Cox analyses were performed again. Subgroup analyses and secondary analyses stratifying patients with different weights and T2DM statuses were also performed.ResultsA total of 2,078 patients were included, of whom 1,412 were overweight (BMI≥25 kg/m2) and 666 were non-overweight (BMI