Study of Blood Test for Detecting Remaining Cancer After Curative Surgery and Chemotherapy in Colorectal Cancer Patients

What this Trial Is About

Colorectal cancer CRC is a common cancer where surgery aims to cure patients, but about 20-25% still experience relapse after surgery. Chemotherapy can lower relapse risk but has significant side effects, so it is only given to those at high risk. This research evaluates circulating tumor DNA ctDNA in blood as a new marker to detect residual cancer and predict relapse risk more accurately than current tumor tissue exams. The overall goal is to confirm ctDNA as a useful clinical tool for monitoring CRC after curative treatment. The study is divided into two parts DANISH.MRD part I focuses on surgery, where blood samples are collected before and after surgery to detect ctDNA. Part II focuses on surveillance, with blood samples collected after adjuvant chemotherapy and during follow-up visits. Patients receive standard care alongside these tests. The study will assess ctDNAs prognostic value, compare ctDNA diagnostic methods, and explore ctDNA levels during and after chemotherapy, as well as their relation to clinical outcomes and imaging results. Participants contribute blood samples at specific times before surgery, 20-30 days after surgery but before chemotherapy, after chemotherapy, and at regular intervals up to three years post-surgery. Tissue from surgery is also collected. Researchers will monitor disease-free survival over three years, compare ctDNA results with CT scans, and analyze molecular characteristics of the cancer. Patients receive standard follow-up care for up to five years. This comprehensive approach aims to improve early detection of relapse and guide treatment decisions.

DANISH.MRD: Danish Assessment of Minimal Residual Disease by Liquid Biopsies