[Application Value of ctDNA-based MRD Dedection 
in Early Stage Non-small Cell Lung Cancer after Radical Surgery]

Lung cancer is the most common malignant tumor in the world, among which non-small cell lung cancer (NSCLC) accounts for about 85% of the total number of lung cancers. The 5-year overall survial (OS) of radical surgery NSCLC patients ranged from 92% in stage Ia1 to 26% in stage IIIb, and the continuously decreasing survival time made it a strong clinical need for precise adjuvant therapy to eradicate molecular residual disease (MRD). At present, circulating tumor DNA (ctDNA) as a molecular indicator of MRD has gradually moved from the laboratory to the clinic. The latest consensus proposes that ctDNA with abundance ≥0.02% can be stably detected in the peripheral blood of perioperative NSCLC patients, which is based on the possibility of ctDNA as an MRD indicator. MRD detection technology supports the possibility of monitoring after radical treatment of NSCLC, and ctDNA can predict the recurrence of the disease earlier than the imaging monitoring after treatment of NSCLC, providing valuable time for timely adjustment of adjuvant therapy. In the studies on early postoperative adjuvant therapy of NSCLC, different guidelines differ on whether appropriate adjuvant therapy should be carried out, while MRD can be used as a more accurate predictor to guide postoperative adjuvant therapy, so that patients can benefit from the disease treatment.
.