Patients initially diagnosed with primary colorectal cancer were enrolled for screening, and plasma samples 1-2 days before radical bowel resection were collected for polygene methylation detection.~The postoperative follow-up was 2 years, and the reexamination included CT/MRI imaging assessment, blood CEA, and dynamic monitoring of plasma ctDNA methylation level. Blood samples were collected for 9 times.~Results analysis: To explore the application value of ctDNA methylation-MRD detection in the prediction of postoperative tumor recurrence risk after radical resection of colorectal cancer; The correlation between preoperative ctDNA methylation level and prognosis of early colorectal cancer.
This study dynamically monitored the prognosis of stage I-IV colorectal cancer patients who could receive radical surgical resection by detecting the levels of polygene methylation in plasma samples from patients with colorectal cancer. In patients with colorectal cancer feasible radical surgery, plasma ctDNA methylation detection was performed before and after surgical treatment and during regular follow-up to explore the predictive effect of plasma ctDNA methylation status at different time points on postoperative recurrence. To explore whether postoperative dynamic monitoring of plasma ctDNA methylation can be used for adjuvant chemotherapy efficacy evaluation and whether it can indicate tumor recurrence and metastasis earlier than imaging examination.