Application of Polygenic Methylation Markers in Postoperative Recurrence Monitoring of Colorectal Cancer

Inclusion Criteria:

1. Newly diagnosed patients with primary colorectal cancer confirmed by histopathology (no restriction on histological type);

2. Patients diagnosed as stage I-III and feasible for radical bowel surgery;

3. Patients diagnosed by stage IV (only colorectal cancer patients with livermetastasis at the time of diagnosis) and feasible radical bowel resection orcomplete resection of liver metastasis;

4. No gender limitation, age ≥18;

5. ECOG score ≤1;

6. Life expectancy ≥5 years;

7. Those who fully understand the study and voluntarily sign the informed consent.

Exclusion Criteria:

1. Blood transfusion was performed during surgery or 2 weeks before surgery;

2. complicated with primary malignant tumors of other organs;

3. With colonic obstruction, intestinal perforation and other symptoms requiringemergency treatment;

4. Colorectal cancer was diagnosed with extrahepatic metastasis;

5. Neoadjuvant therapy (such as radiotherapy and chemotherapy) before radical bowelresection;

6. Radical bowel resection was performed after endoscopic surgery;

7. Concomitant symptoms and/or family history collection suggest hereditary colorectalcancer;

8. serious mental illness or drug abuse;

9. patients with serious heart, lung and vascular diseases who cannot tolerate surgery;

10. pregnant or lactating women;

11. Participate in other interventional clinical investigators within 3 months

12. Poor compliance, unable to complete the study according to the judgment of theresearcher.