CD274 and isolated hemihyperplasia: There are antipituitary antibodies or antipituitary hormone autoantibodies both in the peripheral blood of patients with IgG4-related hypophysitis and PD-1/PD-L1 inhibitor-related IH, suggesting that PD-1/PD-L1 inhibitor-related IH and IgG4-related hypophysitis may have similar pathogenesis.