Comparison of efficacy and safety of second- and third-generation TKIs for non-small-cell lung cancer with uncommon EGFR mutations.

Background: The efficacy of definite for non-small-cell lung cancer (NSCLC) with uncommon epidermal growth factor receptor (EGFR) mutations has been preliminarily demonstrated. However, there is a paucity of data with which to compare the efficacy and safety of second- and third-generation TKIs in patients with NSCLC carrying uncommon EGFR mutations.

Methods: We compared the efficacy and safety of second- and third-generation TKIs in all NSCLC patients in whom next-generation sequencing confirmed uncommon EGFR mutations, including G719X, S768I, and L861Q. The parameters analyzed included the objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS). The rate of treatment-related adverse events (AEs) reflected the safety of these TKIs.

Results: Eighty-four NSCLC patients with uncommon EGFR mutations were enrolled between April 2016 and May 2022 at Zhejiang Cancer Hospital, including 63 treated with second-generation TKIs and 21 treated with third-generation TKIs. The ORR for all patients receiving TKIs was 47.6%, and the DCR was 86.9%. The median PFS for NSCLC patients with uncommon EGFR mutations receiving TKIs was 11.9 months and OS was 30.6 months. There was no significant difference in PFS after treatment with second- or third-generation TKIs (13.3 vs. 11.0 months, respectively, P = 0.910) or in OS (30.6 vs. 24.6 months, respectively P = 0.623). The third-generation TKIs showed no severe toxicity.

Conclusions: The efficacy of second- and third-generation TKIs for NSCLC with uncommon EGFR mutations does not differ, and so can be used to treat NSCLC patients with these mutations.