CTLA4 and hypothyroidism: In a meta‐study, the rates of anti‐CTLA‐4, anti‐PD‐1, and anti‐programmed cell death‐ligand 1 (anti‐PD‐L1)‐induced hypothyroidism were 3.8%, 7.0%, and 3.9%, respectively, and the rate of hypothyroidism caused by nivolumab combined with ipilimumab was as high as 13.2%.4 The rates of anti‐CTLA‐4, anti‐PD‐1, and anti‐PD‐L1 induced hyperthyroidism were 1.7%, 3.2%, and 0.6%, respectively, and the rate of nivolumab combined with ipilimumab caused hyperthyroidism was 8.0%.4