Adjuvant Target Therapy Guided by ctDNA-MRD in Patients With EGFR-mutant II-IIIA Non-small Cell Lung Cancer (ECTOP-1022)

This study plans to conduct ctDNA testing on EGFR mutation-positive stage II-IIIA (N1-N2) NSCLC patients after radical surgery (R0 resection). Patients with positive ctDNA testing will receive standard treatment according to clinical guidelines, while patients with negative ctDNA testing will be assessed based on comprehensive clinical and pathological characteristics. After receiving or not receiving standard adjuvant chemotherapy, patients will be randomly assigned in a 1:1 ratio to either the observation follow-up group (experimental group) or the osimertinib adjuvant treatment group (control group). The aim is to explore whether observation follow-up for patients with negative ctDNA after surgery has a prognosis non-inferior to osimertinib treatment, and to investigate the disease-free survival rate of EGFR mutation-positive stage II-IIIA (N1-N2) NSCLC patients with positive ctDNA after surgery receiving osimertinib adjuvant treatment, providing more precise treatment guidance for adjuvant therapy in this specific type of NSCLC patients with EGFR mutation-positive tumors.