Improved survival in patients with unresectable stage III EGFR ‐mutant adenocarcinoma with upfront EGFR‐tyrosine kinase inhibitors

BACKGROUND: Although epidermal growth factor receptor‐tyrosine kinase inhibitors (EGFR‐TKIs) have been the standard treatment for advanced EGFR‐mutant adenocarcinoma, the effects of upfront EGFR‐TKI use in unresectable stage III EGFR‐mutant adenocarcinoma remain unexplored. Here, we conducted a retrospective study to compare different treatment strategies in these patients. METHODS: From October 2010 to June 2019, patients with unresectable stage III adenocarcinoma who received treatment at a tertiary referral center were enrolled. Patients were classified into three groups: EGFR‐mutant adenocarcinoma treated with concurrent chemoradiotherapy (group 1) or EGFR‐TKI (group 2) and EGFR wild‐type adenocarcinoma treated with concurrent chemoradiotherapy (group 3). Progression‐free survival, progression‐free survival‐2, and overall survival were estimated and compared using Kaplan–Meier and log‐rank tests. RESULTS: A total of 92 patients were enrolled; 10, 40, and 42 patients were assigned to groups 1, 2, and 3, respectively. Patients with EGFR mutations who received upfront EGFR‐TKIs had significantly longer progression‐free and overall survival than those who received upfront concurrent chemoradiotherapy (hazard ratio 0.33 vs. 0.34, p = 0.006 vs. 0.031) according to a Cox model adjusted for possible confounders. Moreover, upfront concurrent chemoradiotherapy did not lead to higher survival rates in patients with EGFR mutations than in those with EGFR wild‐type adenocarcinoma (progression‐free survival; hazard ratio 0.37, p = 0.036; overall survival; hazard ratio 0.35, p = 0.080) by Cox regression analysis. CONCLUSION: This current study suggests that EGFR‐TKIs is a better choice for patients with unresectable stage III EGFR‐mutant adenocarcinoma. However, further randomized studies are required to validate the results.