The efficacy and safety of EGFR-TKI combined with chemotherapy in non-small cell lung cancer (NSCLC) patients with EGFR co-mutation with other oncogenic alterations.

Abstract

e21666 Background: Previous studies indicated primary resistance to EGFR-TKIs might occur in EGFR co-mutation with other oncogenic alterations, including TP53, KRAS, PIK3CA and so on. However, the optimal therapeutic regimens for EGFR co-mutation other oncogenic alterations were still unknown. This respective observation study aimed to evaluate the efficacy and safety of EGFR-TKIs combined with chemotherapy in this sub-population, in order to offer new treatments in clinical practice. Methods: In this retrospectively study, from March 2017 to November 2019 advanced NSCLC patients with EGFR co-mutation with other oncogenic alterations in Medical Oncology of Respiratory, Affiliated Tumor Hospital of Guangxi Medical University were screened for eligibility. All included patients were administrated with EGFR-TKIs combined with platinum-based chemotherapy or EGFR-TKIs monotherapy. The clinicopathological data of the patients, and the efficacy and safety of treatment were accorded for statistic analysis. The Kaplan-Meier method was used to estimate median PFS and OS. For all analyses, p value < 0.05 was considered statistically significant, and confidence interval use 95% confidence level. The primary outcome was Progression-free survival (PFS), and Overall survival (OS), Disease control rate (DCR) and safety profile were considered to be the secondary endpoints. Results: Total 23 patients were enrolled in this retrospectively study. The median age of the combination and monotherapy group was 58.7± 8.8 and 58.9 ± 13.5years, respectively. The frequency of female patients was 53.8% and 40% in monotherapy and combination group, respectively. The median PFS (mPFS) was 5.03 months (95% CI: 1.16- 8.9) and not reach in combination therapy group (P = 0.004). No significantly different in mOS was observed in two groups (P = 0.244). The DCR was 92.3% and 100% in monotherapy and combination group, respectively. In combination group, the common adverse events of grade 1 or 2 were adverse reactions of the blood system and rash (40%). Treatment-related grade 3 or 4 toxicity appeared in 3 patients and no patients harbored treatment-related above grade 4 side effects. No cases of treatment-related death occurred. Conclusions: EGFR-TKIs combined with chemotherapy was effective in NSLCL patients with EGFR co-mutation with other oncogenic alterations and side-effects were tolerable. The outcomes of this study should be confirmed by prospective clinical trials in future.