Colonoscopy can be performed for the first time within 6 months after colon cancer surgery, which means that colon cancer patients have different times to review colonoscopy after surgery or endoscopic surgery. For progressive colon cancer, after surgery, there is a certain trauma and it takes some time for patients to repair, so often in 6 months after surgery, patients are allowed to come for colonoscopy to see the anastomosis, patency and so on; if doing endoscopic removal of early colon cancer or colon precancerous lesions, depending on the situation, often in 2-3 months you can review colonoscopy for the first time. However, it is not only 1 review, but also continuous colonoscopy or fecal occult blood test should be done every year afterwards, and patients should be followed up and followed up for a long time. If new lesions are found during the review, they should be treated promptly.