Radiation lung injury: Treatment-related injury is often encountered in the course of lung cancer radiation therapy, just like surgery will leave scars, lung tissue will produce irreversible scarring changes after a certain dose of radiation therapy, the acute phase is radiation pneumonia, and the chronic phase is radiation pulmonary fibrosis. The occurrence of radiation lung injury is related to the dose and volume of the irradiated lung. The dose and volume of the irradiated lung should be minimized during radiation therapy so that it does not exceed the tolerated dose, which can reduce the possibility of radiation lung injury. However, even very cautious radiotherapy carries the risk of radiation lung injury, and the incidence of radiation pneumonitis above grade II in lung cancer radiotherapy at the M.D. Anderson Cancer Center in the United States is as high as 60% or more. However, after aggressive treatment, the survival of patients receiving aggressive radiotherapy is significantly longer than that of patients receiving conservative treatment. Thus, fear of radiation pneumonia should not prevent patients from receiving radiation therapy. Of course, the risks of radiation therapy should be minimized. Most cases of radiation pneumonia can be cured with aggressive treatment. The possibility of death from radiation pneumonia from lung cancer radiation therapy is reported in the literature to be less than 2%, similar to the risk of surgical treatment. If the extent of radiation lung injury is relatively limited, most patients can recover with aggressive treatment, but if the extent of radiation lung injury is too large, the patient is still at greater risk of serious consequences. Treatment for radiation pneumonia is mainly high-dose hormones, with methylprednisolone being more effective than dexamethasone and prednisone, and symptomatic treatment with sputum, asthma, and antioxidants. The specific treatment plan should be determined according to the patient’s specific situation.