Abstract
It remains undetermined whether there is an explicit association between the epidermal growth factor receptor (EGFR) gene mutation status and chemotherapy efficacy in non-small cell lung cancer (NSCLC) patients with advanced stages. Thus, the aim of the present retrospective study was to investigate the possible association between EGFR gene mutation status and the efficacy of first-line chemotherapy in patients with advanced NSCLC. In total, 52 patients who were diagnosed with NSCLC at Changzhou Tumor Hospital (Changzhou, China) from January 2015 to December 2018 were enrolled. All 52 patients received pemetrexed combined with platinum chemotherapy, for 21 days per cycle. After two cycles of treatment, the short-term clinical efficacy was assessed according to the Response Evaluation Criteria in Solid Tumours 1.1 guidelines. The objective response rate (ORR), disease control rate (DCR) and progression-free survival (PFS) rate were calculated at the end of the study (December 31, 2019). These patients also underwent second-generation gene sequencing before the potential association between mutations in the EGFR gene and chemotherapy efficacy was analyzed. In this group of patients, 25 cases (48.1%) were found to be harboring EGFR gene mutation, whilst 27 cases (51.9%) expressed wild-type EGFR. After receiving the first-line chemotherapy regimen, the ORR was determined to be 36.5%, the DCR was 71.2%, whereas the PFS period was 207 days. Following first-line chemotherapy, the DCR of patients with EGFR mutations (52%) was higher compared with those in patients harboring the wild-type EGFR (22%). By contrast, the PFS (260 days) of patients with EGFR mutations was longer compared with those in patients harboring wild-type EGFR (100 days). These differences were statistically significant (P<0.05). Multivariate analysis revealed that EGFR gene mutation was an independent predictor of PFS in patients with advanced NSCLC (P<0.05). To conclude, data from the present study suggest that EGFR gene mutation has independent predictive value for the efficacy of first-line chemotherapy in patients with advanced NSCLC.