PDCD1 and hypothyroidism: If in 2017 Barroso-Sousa R. et al. reported a 3.8% incidence of all grade hypothyroidism with anti-CTLA-4 antibodies, 7% with anti-PD-1, and 13.2% with a combination [68], in 2023, Won S.Y. et al. published an increased incidence of immune-related hypothyroidism of 4.4% with CTLA-4 inhibitors, 13.7% with PD-1 inhibitors, and a decreased incidence of 9.7% with an anti-CTLA-4/PD-L1 antibody combination [69].