2024 Asia Conference on Lung Cancer (ACLC) - Poster & ePosters-PP01.74

PP01.74 - Yiliang Liu

Pdf Summary

This prospective study explored the prognostic value of molecular residual disease (MRD) monitoring in limited-stage small-cell lung cancer (LS-SCLC) following chemoradiotherapy. Conducted at a single center, the study enrolled 29 patients who provided serial circulating tumor DNA (ctDNA) samples assessed using targeted next-generation sequencing. These samples were collected at defined time points: within four weeks after chemoradiotherapy (landmark) and every three months thereafter (longitudinal).<br /><br />The primary objectives were to determine the positive predictive value (PPV) and negative predictive value (NPV) of ctDNA-based MRD for disease recurrence. Landmark MRD testing showed a sensitivity of 57.1% for predicting relapse, which increased to 92.3% with longitudinal MRD monitoring. The PPV of detectable MRD at landmark was 88.9%, and the NPV was 53.8%. These values improved to 70.6% and 87.5%, respectively, with longitudinal monitoring.<br /><br />Importantly, patients with undetectable MRD at landmark points exhibited better progression-free survival (PFS) than those with detectable MRD, with median PFS of 333 days compared to 190 days. The results were even more favorable with longitudinal monitoring, where the median PFS was unreached compared to 275 days. MRD detection predominantly occurred 3 to 6 months post-landmark point, typically preceding imaging-based recurrence by about 120 days in 88.2% of cases.<br /><br />Overall, the study confirms that ctDNA-based MRD monitoring is a valuable prognostic tool for predicting disease relapse in LS-SCLC patients post-chemoradiotherapy. Detectable MRD serves as an early indicator of relapse, often before imaging can confirm recurrence. This highlights the potential of MRD monitoring to improve patient management and outcomes in LS-SCLC.

Keywords

molecular residual disease

small-cell lung cancer

chemoradiotherapy

circulating tumor DNA

next-generation sequencing

prognostic tool

disease recurrence

progression-free survival

positive predictive value

negative predictive value