CD274 and pneumonitis: ,46,49,51 BMI showed a weak but significant positive correlation with pneumonitis risk (HR = 1.03, 95% CI = 1.01–1.05, p = 0.001), with patients having BMI ≥30 at significantly higher risk (HR = 2.24, 95% CI = 1.12–4.48, p = 0.02), consistent with Akkad et al.25The role of PD-L1 expression levels and TNM staging in pneumonitis risk remains unclear.