High incidence of immune checkpoint inhibitor-induced pneumonitis in patients with non-small cell lung cancer and interstitial pneumonia, regardless of honeycomb lung or forced vital capacity: results from a multicenter retrospective study.

BACKGROUND

Interstitial pneumonia (IP) is a common comorbidity with poor prognosis in patients with non-small cell lung cancer (NSCLC) and a risk factor for immune checkpoint inhibitor (ICI)-induced pneumonitis. This study aimed to assess the incidence, severity, and risk factors of ICI-induced pneumonitis in patients with NSCLC and idiopathic IP.

METHODS

This multicenter, retrospective study involved patients with advanced or recurrent NSCLC and comorbid idiopathic IP and receiving ICI monotherapy as the second or subsequent line. A board-certified radiologist centrally reviewed all computed tomography images at baseline and at the onset of pneumonitis. Logistic regression analysis with clinical, laboratory, and radiological variables was used to examine the risk factors for pneumonitis.

RESULTS

This study included 65 patients with a median age of 71 years, 98.5% of whom had a smoking history. Three ICIs were used and a median of three cycles. Honeycomb lung was present in 23.1% of the patients, and the median % forced vital capacity (FVC) was 95.0%. Notably, 23.1% of the patients exhibited all-grade pneumonitis and 15.4% exhibited grade ≥ 3 pneumonitis. No significant risk factors for pneumonitis were identified after univariate logistic regression analysis. The incidence and severity of ICI-induced pneumonitis did not differ between patients with and without honeycomb lung or with FVC ≥ 80% versus < 80%, respectively.

CONCLUSION

In this retrospective analysis of patients with NSCLC, the risk of ICI-induced pneumonitis did not differ based on radiologic patterns of comorbid IP, presence or absence of honeycomb lung, or pulmonary function tests.