Common Medical Comorbidities Influence Pneumonitis Risk After Chemoradiotherapy and Durvalumab Maintenance in Stage...

Approximately 25% of patients with non-small cell lung cancer (NSCLC) present with Stage III disease. The standard treatment for inoperable patients involves definitive chemoradiotherapy (CRT) followed by 12 months of maintenance durvalumab. However, the incidence of pneumonitis-an adverse effect of this regimen-affects a significant proportion of patients. This study aimed to identify predictors of pneumonitis in a large cohort of patients with unresectable Stage III NSCLC receiving CRT and durvalumab, with a focus on common medical comorbidities.

Using data from the Veterans Health Administration's Corporate Data Warehouse, we identified 1,524 patients who received the standard regimen between June 2017 and July 2023. Pneumonitis was assessed via ICD codes and severity determined using National Cancer Institute criteria. We analyzed associations between pneumonitis and various covariates including age, comorbidities, and medication use.

Our findings indicated a cumulative pneumonitis incidence of 14.5%, with 7.68% of cases classified as grade 3 or higher. Significant risk factors included advanced age, higher Charlson Comorbidity Index (CCI), prior pneumonia, diabetes, obesity, and antibiotic use, particularly cephalosporins and macrolides. Notably, severe chronic obstructive pulmonary disease (COPD) and uncontrolled diabetes were associated with an increased risk of pneumonitis. In contrast, prior tobacco use and better ECOG performance status (lower score) were protective.

These results highlight the complex interplay between comorbid conditions, medication, and pneumonitis risk in patients undergoing CRT and durvalumab therapy. Further research is needed to explore these relationships and potentially inform strategies to mitigate pneumonitis risk.