Reducing radiation pneumonitis in lung cancer patients: from Chinese expert consensus to practice.

Background: Radiation pneumonitis (RP) is a common but severe complication in lung cancer patients undergoing thoracic radiotherapy, significantly impacting patient survival and quality of life. Currently, standardized clinical protocols for predicting, preventing, and managing RP remain insufficiently applied, and the clinical effectiveness of consensus-driven management guidelines in reducing RP remains unclear. This study aimed to clarify whether implementing the Chinese expert consensus on RP could effectively decrease the incidence and severity of RP, and identify independent clinical risk factors.

Methods: This retrospective comparative study included 616 lung cancer patients who underwent thoracic radiation therapy at Shanghai Pulmonary Hospital between August 2020 and January 2022. Patients were divided into two groups based on treatment periods relative to the implementation of consensus recommendations in August 2021: the pre-consensus group (treated from August 2020 to July 2021) and the post-consensus group (treated from August to January 2022). The consensus-driven interventions included three key strategies: strict limitation of planning target volume (PTV) margins, individualized lung dose constraints, and standardized steroid treatment protocols. RP incidence and severity were assessed over a 12-month follow-up according to the Common Terminology Criteria for Adverse Events (CTCAE, v5.0). Multivariate logistic regression was conducted to identify predictors for severe RP (SRP, grade ≥3).

Results: The clinical characteristics were comparable between the pre- and post-consensus groups. After implementing consensus recommendations, the overall incidence of RP decreased significantly (67.3% vs. 55.2%, P=0.003), and grade ≥3 RP markedly reduced (9.9% vs. 3.4%, P=0.005). Multivariate logistic regression analysis identified independent predictors for grade ≥3 RP: pre-existing interstitial lung disease (ILD), forced expiratory volume in 1 second (FEV1), diffusing capacity for carbon monoxide (DLCO), lymphocyte baseline counts, limited PTV margin, standardized steroids use, radiotherapy dose and V20.

Conclusions: Risk factor prevention and standardized treatment could decrease the occurrence of SRP. Clinicians should implement the recommendations in the RP management consensus in clinical practice. Special attention should be given to patients with identifiable risk factors such as pre-existing ILD, compromised lung function, high radiotherapy dose and low lymphocyte baseline counts, to improve patient prognosis and treatment safety.