The combination of immune checkpoint inhibitor and chemotherapy may be efficacious for advanced non-small cell lung cancer with near-loop insertions of <i>EGFR</i> exon 20: A retrospective analysis

ObjectiveThe sensitivity of immune checkpoint inhibitors (ICIs) as monotherapy is low in non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (<i>EGFR</i>) exon 20 insertion mutations (ex20ins). This study aims at investigating the effectiveness of the combination of ICI and chemotherapy (ICI-combined regimen) in a real-world population of NSCLC patients harboring near-loop insertions of <i>EGFR</i> exon 20.MethodsWe conducted a retrospective study of advanced NSCLC with <i>EGFR</i> ex20ins from April 2016 to March 2021 at Guangdong Provincial People's Hospital, Southern Medical University, China. A total of 126 cases of <i>EGFR</i> ex20ins were screened from 1610 patients with advanced NSCLC harboring <i>EGFR</i> mutations and 62 cases were further analyzed for different therapeutic efficacy.ResultsThe first-line ICI-combined regimen showed marked efficacy for near-loop insertions of <i>EGFR</i> exon 20, with an ORR of 71.4% and a mPFS of 11.5 months, compared to ORRs of 12.5% for traditional targeted therapy (<i>P </i>= .003) and 18.8% for chemotherapy (<i>P </i>= .013). The first-line mPFS of traditional <i>EGFR</i>-TKIs and chemotherapy were only 5.6 and 5.8 months, respectively. Similar results were observed for any-line therapy of ICI-combined regimen, with an ORR of 80%. The median progression-free survival (PFS) of any-line therapy of ICI-combined regimen was 11.5 months, which were significantly longer than that of traditional targeted therapy (4.5 months, <i>P </i>= .026) and chemotherapy (5.0 months, <i>P </i>= .013).ConclusionsICI-combined regimen may be superior compared to targeted therapy and chemotherapy for advanced NSCLC with near-loop insertions of <i>EGFR</i> exon 20. Further exploration is warranted to confirm the efficacy of ICI-combined regimen.