Efficacy Differences of First-line EGFR-TKIs Alone vs. in Combination with Chemotherapy in Advanced Lung Adenocarcinoma Patients with Sensitive EGFR Mutation and Concomitant Non-EGFR Genetic Alteration(s)
Abstract Objective: To explore whether EGFR-TKI combined with chemotherapy would benefit patients with advanced lung adenocarcinoma with both sensitive EGFR mutation and concomitant non-EGFR genetic alterations. Materials and Methods: Cases of advanced lung adenocarcinoma with EGFR mutation combined with concomitant non-EGFR genetic alterations were retrospectively collected. And the patients were required to receive first-line EGFR-TKI and chemotherapy combination or EGFR-TKI monotherapy. Demographic, clinical and pathological data were collected, and the electronic imaging data were retrieved to evaluate the efficacy and time of disease progression. Survival data were obtained through face-to-face or telephone follow-up. The differences between the two groups in objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS) and overall survival (OS) were investigated. Results: 107 patients were included, including 63 in the combination therapy group and 44 in the monotherapy group. The ORR were 78% and 50% (P =0.003), and DCR were 97% and 77% (P =0.002), respectively. At a median follow-up of 13.7 months, a PFS event occurred in 38.1% and 81.8% of patients in the two groups, with median PFS of 18.8 and 5.3 months, respectively (P <0.0001). Median OS was unreached in the combination group, and 27.8 months in the monotherapy group (P =0.31). According to the Cox multivariate regression analysis, combination therapy was an independent prognostic factor of PFS. Conclusion: In patients with EGFR-mutant advanced lung adenocarcinoma with concomitant non-EGFR genetic alterations, combination of TKI and chemotherapy was significantly superior to EGFR-TKI monotherapy, which should be the preferred treatment option.