Real-World Survival Outcomes Based on EGFR Mutation Status in Chinese Patients With Lung Adenocarcinoma After Complete Resection: Results From the ICAN Study

Abstract

IntroductionThe adjuvant treatment of patients with resected lung adenocarcinoma (LUAD) remains unstandardized. We analyzed the survival outcomes of these patients based on EGFR mutation status and adjuvant chemotherapy treatment. MethodsThis noninterventional real-world study (ICAN) enrolled Chinese patients with resected stages I to III LUAD from April 8, 2010, to December 31, 2010. Tumor EGFR mutation status and 3-year disease-free survival (DFS) were determined. The extension phase provided long-term follow-up with overall survival (OS) as the primary end point. Secondary end points included DFS and prognostic factors of survival. Survival outcomes based on adjuvant chemotherapy treatment, EGFR mutation status, and postoperative stage were analyzed post hoc. ResultsAmong 568 patients in the ICAN cohort, 472 continued to the extension phase and remained eligible. The 3-year DFS rate was 58.8%. In the extension cohort, 260 patients (55.1%) had EGFR-mutant disease and 207 (43.9%) received adjuvant chemotherapy. At a median follow-up of 109.0 (95% confidence interval [CI]: 106.6–111.4) months, median OS and DFS were 103.3 (95% CI: 101.7–104.9) and 67.4 (95% CI: 49.7–85.2) months, respectively. The 5-year OS and DFS rates were 68.9% (95% CI: 64.3–73.6) and 52.9% (95% CI: 48.2–57.7), respectively. EGFR wild-type disease was a significant independent predictor of worse OS (HR = 1.24, 95% CI: 1.07–1.44, p= 0.004) based on the Cox regression analysis of common factors. Post hoc subgroup analysis revealed that survival outcomes were not significantly different with adjuvant chemotherapy regardless of EGFR mutation status across all postoperative stages. ConclusionsEGFR mutations are common in operable LUAD, and recurrence and mortality after resection were considerable. Adjuvant chemotherapy did not improve survival outcomes, regardless of EGFR mutation status and postoperative stage.