Hung SK, et al. - A population-based surgical cohort study is performed to investigate whether postoperative irradiation increases occurrence of severe pneumonopathy in lung cancer patients. A high risk of hospitalised pneumonopathy is observed in irradiated patients, especially in elderly males with chronic obstructive pulmonary disease (COPD) and chronic kidney disease (CKD). Close clinical surveillance and aggressive pneumonia/pneumonitis prevention should be considered for these patients. Especially for younger CKD patients, further examinations are required to define underlying biological mechanisms.