Predictive value of tumor genetic alteration profiling for chemotherapy and EGFR-TKI treatment in advanced NSCLC

Previous studies have suggested that a variety of tumor driver genetic alterations affected the treatment efficacy of chemotherapy and epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) in advanced non-small cell lung cancer (NSCLC). The present study aimed to investigate the association between the tumor genetic alteration landscape and the treatment outcome of first-line chemotherapy and EGFR-TKIs in advanced NSCLC. A total of 94 patients with advanced NSCLC were recruited. All patients received first-line chemotherapy and/or EGFR-TKIs (either first- or second-generation EGFR-TKI, or third-generation EGFR-TKI) alone or sequentially. Prior to chemotherapy and/or EGFR-TKI treatment, plasma, effusion and/or tumor tissues from the included patients were subjected to next-generation sequencing, targeting 59 genes. The results indicated that the positive genetic alteration status prior to first-line chemotherapy was associated with prolonged progression-free survival (PFS) time compared with the negative status [9.1 vs. 4.0 months; hazard ratio (HR)=6.68; 95% CI, 2.25–19.82; P=0.001). Furthermore, patients with EGFR activating mutation harboring concomitant alterations exhibited a shorter PFS (11.1 vs. 7.4 months; HR=2.14; 95% CI, 1.03–4.44; P=0.04) and overall survival (OS) time [not reached (NR) vs. 32.8 months; HR=4.30; 95% CI, 1.41–13.16; P=0.01] than those without concomitant alterations, with first- and second-generation EGFR-TKI treatment. Similarly, patients with T79M mutation harboring concomitant alterations exhibited a shorter PFS (15.6 vs. 3.6 months; HR=9.48; 95% CI, 2.29–39.28; P=0.002) and OS time (NR vs. 32.8 months; HR=4.85; 95% CI, 1.16–20.29; P=0.03) with osimertinib treatment. Taken together, the results demonstrated that positive genetic alteration status predicted greater efficacy of first-line chemotherapy, while concomitant genetic alterations were associated with poor treatment outcome for first- or second-generation EGFR-TKI and third-generation EGFR-TKI treatment.