1.Guidelines for postoperative follow-up of colorectal cancer: (1)History and signs: every 3-6 months for 2 years; then every 6 months for 5 years. (2) Monitoring CEA: every 3-6 months for 2 years; then every 6 months for 5 years. (3) Review abdominal and pelvic CT once a year for 3 years. (4) Perform colonoscopy 1 year after surgery, and then as needed. 2.Guidelines for postoperative follow-up of gastric cancer: (1)Within 1 year after surgery, come to outpatient clinic for review every 3 months. In the second year, follow up once every six months. After that, follow up once a year. (2) During the review, we should find out whether there is any mass in the abdomen, whether the liver is enlarged, the condition of the umbilicus, whether there are enlarged lymph nodes in the left supraclavicular fossa, and whether a mass can be palpated in the anterior rectal recess. Chest X-ray and abdominal ultrasound should be performed once every six months, and other special examinations such as CT and gastroscopy should be performed when necessary to clarify whether there is recurrence or distant metastasis. (3) During the follow-up visit, we should also pay attention to the patient’s quality of life, such as the number of meals, food quantity, whether there is dumping syndrome or bile reflux, weight change, whether there is anemia, whether the life and living is normal, physical strength, whether the patient can resume normal work, etc.