Interestingly, a recent meta-analysis of 38 randomized clinical trials comprising 7,551 patients who underwent checkpoint inhibitor immunotherapy found a consistent reduction in the incidence of thyroiditis and insulin-deficient diabetes for single-agent anti-PD-1/PD-L1 when compared with anti-CTLA-4 monotherapy (28–30, 32). This evidence concerns the gene CTLA4 and thyroiditis.