Abnormalities on baseline chest imaging are risk factors for immune checkpoint inhibitor associated pneumonitis

Danielle Stahlbaum; Renea Jablonski; Mary E Strek; Christine M Bestvina; Mei-Yin Polley; Pankti Reid

doi:10.1016/j.rmed.2023.107330

Abnormalities on baseline chest imaging are risk factors for immune checkpoint inhibitor associated pneumonitis

Respir Med. 2023 Oct:217:107330. doi: 10.1016/j.rmed.2023.107330. Epub 2023 Jun 28.

Authors

Danielle Stahlbaum¹, Renea Jablonski², Mary E Strek³, Christine M Bestvina⁴, Mei-Yin Polley⁵, Pankti Reid⁶

Affiliations

¹ Section of Pulmonary and Critical Care, Department of Medicine, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, MI, 48109, USA. Electronic address: danidan@med.umich.edu.
² Section of Pulmonary and Critical Care, Department of Medicine, University of Chicago, Chicago, IL, USA. Electronic address: reneaj@medicine.bsd.uchicago.edu.
³ Section of Pulmonary and Critical Care, Department of Medicine, University of Chicago, Chicago, IL, USA. Electronic address: mstrek@medicine.bsd.uchicago.edu.
⁴ Section of Hematology and Oncology, Department of Medicine, University of Chicago, Chicago, IL, USA. Electronic address: cbestvina@medicine.bsd.uchicago.edu.
⁵ Department of Public Health Sciences, University of Chicago, Chicago, IL, USA. Electronic address: mcpolley@bsd.uchicago.edu.
⁶ Section of Rheumatology, Department of Medicine, University of Chicago, Chicago, IL, USA. Electronic address: Pankti.reid@uchospitals.edu.

PMID: 37385460
DOI: 10.1016/j.rmed.2023.107330

Abstract

Background: Chronic lung disease is a proposed risk factor for immune checkpoint inhibitor pneumonitis (ICI-pneumonitis); however, data is sparse regarding the impact of pre-existing lung disease and baseline chest imaging abnormalities on the risk of developing ICI-pneumonitis.

Methods: We conducted a retrospective cohort study of patients with ICI treatment for cancer from 2015 to 2019. ICI-pneumonitis was determined by the treating physician with corroboration via an independent physician review and exclusion of alternative etiologies. Controls were patients treated with ICI without a diagnosis of ICI-pneumonitis. Fisher's exact tests, Student's t-tests, and logistic regression were used for statistical analysis.

Results: We analyzed 45 cases of ICI-pneumonitis and 135 controls. Patients with abnormal baseline chest CT imaging (emphysema; bronchiectasis; reticular, ground glass and/or consolidative opacities) had increased risk for ICI-pneumonitis (OR 3.41, 95%CI: 1.68-6.87, p = 0.001). Patients with gastroesophageal reflux disease (GERD) (OR 3.83, 95%CI: 1.90-7.70, p = < 0.0001) also had increased risk for ICI-pneumonitis. On multivariable logistic regression, patients with abnormal baseline chest imaging and/or GERD remained at increased risk for ICI-pneumonitis. Eighteen percent of all patients (32/180) had abnormal baseline chest CT consistent with chronic lung disease without a documented diagnosis.

Conclusion: Patients with baseline chest CT abnormalities and GERD were at increased risk for developing ICI-pneumonitis. The large proportion of patients with baseline radiographic abnormalities without a clinical diagnosis of chronic lung disease highlights the importance of multidisciplinary evaluation prior to ICI initiation.

Keywords: Cancer immunotherapy; Immune checkpoint inhibitor pneumonitis; Immune related adverse events; Pneumonitis.