70P Combination of EGFR-TKI and chemotherapy versus EGFR-TKI monotherapy as neoadjuvant treatment of stage III-N2 EGFR-mutant non-small cell lung cancer

This study explored the potential benefits of combining first-generation EGFR-TKI with chemotherapy as a neoadjuvant treatment of stage Ⅲ-N2 EGFR-mutant NSCLC patients. The medical records of patients with Ⅲ-N2 EGFR-mutant NSCLC who received neoadjuvant therapy with EGFR-TKI at Shanghai Chest Hospital from October 2011 to October 2022 were retrospectively reviewed. Patients with stage III-N2 EGFR-mutant NSCLC who received first-generation TKI combined with chemotherapy as neoadjuvant treatment were included in the observation group, and those who received EGFR-TKI monotherapy were included in the control group. A total of 74631 EGFR-mutant NSCLC patients were screened, and 60 patients were included, 7 of whom did not undergo surgery after neoadjuvant targeted therapy. Of the remaining 53 patients, 15 received first-generation EGFR-TKI combined with chemotherapy as neoadjuvant treatment, and 38 received EGFR-TKI monotherapy. The median follow-up time was 44.12 months. The ORR was 50.0% (9/18) in the combination group and 40.5% (17/42) in the monotherapy group (p =0.495). MPR was observed in 20.0% (3/15) and 10.5% (4/38) of patients in the combination and monotherapy groups, respectively (p =0.359). No patients achieved PCR in the combination group, while three attained PCR in the monotherapy group. The two groups did not differ in N2 downstaging rate (p =0.459). The median DFS was not reached in the combination group, while it was 23.6 months (95% CI: 8.16-39.02) in the monotherapy group (p = 0.832). Adverse events observed were consistent with those commonly associated with the two treatments. Combination therapy with first-generation EGFR-TKI and chemotherapy could be considered a neoadjuvant treatment option for NSCLC patients of EGFR-mutant stage III-N2, exhibiting acceptable toxicity. However, regarding short-term efficacy, combination therapy did not demonstrate superiority over EGFR-TKI monotherapy. Long-term follow-up is warranted for a more accurate assessment of the DFS and OS.