CD274 and pneumonitis: The incidence rates for adverse events of applied PD-L1 inhibitor therapy were as follows: the incidence rate of grades 1–5 cough was 0.162 (95%CI: 0.065–0.402, I2 = 85.22%); the incidence rate of grades 1–5 pneumonitis was 0.106 (95%CI: 0.036–0.271, I2 = 83.77%); the incidence rate of grades 1–5 upper respiratory tract infection was 0.053 (95%CI: 0.000-0.111, I2 = 0%); the incidence rate of grades 3–5 pneumonitis was 0.050 (95%CI: 0.020–0.091, I2 = 84.23%).