Monitoring ctDNA Levels to Predict Response and Outcomes of Total Neoadjuvant Therapy in Stage II-III Rectal Cancer

What this Trial Is About

Researchers are conducting a prospective observational study to evaluate circulating tumor DNA ctDNA levels in blood samples of patients with stage II-III rectal cancer undergoing total neoadjuvant therapy TNT. The study aims to assess ctDNA detection rates before, during, and after TNT, explore the relationship between ctDNA and imaging results with pathological complete response pCR, and examine how post-TNT ctDNA levels relate to disease-free survival. Participants will have blood samples collected at three key timepoints before TNT, mid-treatment, and after TNT but before surgery, to analyze ctDNA changes. Additionally, tumor biopsy samples are collected before treatment and after surgery to compare mutational profiles. The study also gathers clinical data including MRICT scan images, tumor stage, and pathology reports to correlate with ctDNA and treatment response. During the study, participants will undergo blood draws and imaging assessments at specified intervals, along with clinical evaluations and pathological examinations of tumor tissue. Researchers will monitor disease-free survival for two years following treatment. Outcome measures include ctDNA detection rates, correlation with imaging and pathological response, and long-term survival data, providing a comprehensive picture of ctDNAs role in monitoring TNT efficacy.

ctDNA Monitoring to Predict the Efficacy of TNT for Rectal Cancer