PDCD1 and hypophysitis: Hypophysitis occurs in 1.8% to 17% of patients receiving ipilimumab, either alone or in combination with a PD-1/PD-L1 inhibitor, while the incidence of hypophysitis in the setting of PD-1/PD-L1 monotherapy is reported to range between 0.5% and 1.0% [23].