Second-line therapy with first- or second-generation tyrosine kinase inhibitors in EGFR-mutated non-small cell lung cancer patients with T790M-negative or unidentified mutation.

Abstract

BackgroundT790M mutation causes resistance to tyrosine kinase inhibitors (TKIs) in approximately 49% of patients with epidermal growth receptor‐mutant non‐small cell lung cancer (NSCLC). The cause of resistance in the remaining half of the cases is a minor mutation or unknown. Here, we conducted a retrospective study of epidermal growth receptor‐mutant NSCLC patients with T790M‐negative or an unidentified mutation to appraise the therapeutic response to first‐ or second‐generation tyrosine kinase inhibitors as a second‐line treatment.MethodsThe study included 39 patients treated in our institution from April 2012 through March 2020 with second‐line tyrosine kinase inhibitors or chemotherapy after completing a first‐line therapy with tyrosine kinase inhibitors.ResultsThe patients were allocated to two groups: chemotherapy (n = 28) and a tyrosine kinase inhibitor (n = 11) groups. The median progression‐free survival (PFS) was 5.4 months in the chemotherapy group and 3.4 months in the tyrosine kinase inhibitor group (p‐value = 0.36), while the median overall survival (OS) was 16.1 months in the chemotherapy group and 12.8 months in the tyrosine kinase inhibitor group (p‐ value = 0.20). This study showed no significant difference in PFS and OS between the chemotherapy and tyrosine kinase inhibitor groups.ConclusionsThese observations suggest that first‐ and second‐generation tyrosine kinase inhibitors are not recommended for second‐line treatment in epidermal growth factor receptor‐mutated NSCLC patients with T790M‐negative mutation who have received tyrosine kinase inhibitors as first‐line treatment.