Efficacy and Safety of Chemoimmunotherapy in Patients With Advanced Non-small Cell Lung Cancer With Pre-existing...

Establishing the suitability of initiating immune checkpoint inhibitor (ICI) therapy in patients with lung cancer and coexisting interstitial pneumonia (IP) is challenging. Real-world evidence on the efficacy and safety of ICIs in such patients is urgently needed to inform clinical practice.

This retrospective study evaluated the effects of ICI administered to 79 patients with advanced or recurrent non-small cell lung cancer (NSCLC) and programmed death ligand 1 (PD-L1) tumor proportion scores of 1-49%, who had pre-existing IP. These patients received first-line therapy comprising an ICI with chemotherapy or chemotherapy alone at 18 institutions in Japan between March 2017 and June 2022.

Twelve patients received ICI plus chemotherapy (chemoimmunotherapy group) as first-line treatment, and 67 received chemotherapy alone (chemotherapy group). Only brain metastases were significantly more frequent in the chemoimmunotherapy group; no other differences in patient backgrounds between the two groups were observed. Overall survival (OS) and progression-free survival did not differ between the two groups. After propensity score matching, chemoimmunotherapy significantly prolonged OS compared to chemotherapy alone (25.3 months vs. 9.6 months, p=0.033), without significant differences in incidences of severe adverse events, including pneumonitis. In the analysis of patients who received ICI up to second-line treatment, ICI therapy was associated with prolonged OS compared to non-ICI treatment (29.8 months vs. 16.3 months, p=0.012).

Early use of immunotherapy for patients with advanced NSCLC with low PD-L1 expression and coexisting IP may improve prognosis.