With the increase of people’s health awareness, many middle-aged and elderly people will have regular medical checkups including blood tests, abdominal ultrasound, chest X-ray, etc., but few people will take the initiative to do intestinal health checkups. Colorectal cancer is a preventable and treatable malignancy. Due to the effectiveness of preventive measures and health education, the incidence and mortality rate of colorectal cancer in the United States are now in a declining stage, while the incidence and mortality rate of colorectal cancer in China are in a rapidly increasing stage. The symptoms of colorectal cancer (i.e. colorectal cancer) are insidious, and patients may not have obvious local symptoms in the early stage of the disease or even in the late stage of the disease, so that many patients have already reached the middle and late stage when they are diagnosed, and the treatment effect is greatly reduced. Therefore, health check of the intestinal tract is especially important. As early colorectal cancer has no specific symptoms, how to detect colorectal cancer at an early stage through physical examination? Many people refuse to undergo colonoscopy because of the fear of colonoscopy, which causes many clinical cases of colorectal cancer not to be diagnosed and treated at an early stage and miss the opportunity of treatment. In fact, with the development of medical technology and the improvement of physicians’ proficiency, colonoscopy has become quite convenient and most people can tolerate and complete the examination. For those who have never had a colonoscopy in their life, the first colonoscopy is best to start from the age of 40. Colorectal cancer is highly prevalent and colonoscopy is irreplaceable Colorectal cancer is a preventable and treatable malignancy. Due to the effectiveness of preventive measures and health education, the incidence and mortality rate of colorectal cancer in the United States are now in a declining stage, while the incidence and mortality rate of colorectal cancer in China are in a rapidly increasing stage. According to statistics, there are 130,000 new cases of colorectal cancer a year nationwide, and the trend is younger. In large cities, the incidence rate of colorectal cancer is the third highest among men and the second highest among women. Colonoscopy is the most effective and irreplaceable means to detect early colorectal cancer. Colonoscopy not only can clearly observe the intestinal tract, but also can take suspicious lesions for pathological examination under direct vision, which is conducive to the detection and confirmation of early stage and microscopic colorectal cancer. It can also perform minimally invasive treatment on some intestinal lesions, such as direct microscopic removal of benign lesions such as colorectal polyps, microscopic hemostasis of intestinal bleeding, and removal of colorectal polyps to interrupt their transformation to cancer. Since colorectal cancer symptoms are more insidious, there is no difference in the polyp detection rate between symptomatic and asymptomatic people. Therefore, it is especially important to have an early bowel health check. Those who have a family history of colorectal cancer or have changes in stool habits, blood in stool, weight loss, or unexplained abdominal pain, especially those over 40 years old, should undergo a routine screening. Notes on colonoscopy It is sufficient to take a laxative to cleanse the bowel the night before the colonoscopy. During the examination, the patient may have different degrees of distension or pulling sensation, but as long as the patient can calmly follow the doctor’s instructions and actively cooperate, most people can tolerate and complete the examination. With the development of medical technology and the improvement of physicians’ operational proficiency, the discomfort of colonoscopy has been greatly reduced, and the examination time has also been greatly shortened. Generally speaking, a skilled and experienced endoscopy center can complete a colonoscopy in 5-10 minutes. The colonoscopy experience has a lot to do with the doctor’s operating skills and the relaxation of the person being examined, the more relaxed the examination is, the smoother it is. Some people who are afraid can also choose to perform “painless colonoscopy” under anesthesia. Note after the examination: 1, some patients have abdominal pain, abdominal distension and other symptoms after the examination, do not need to be too nervous, can gently abdomen, slight walking, to be relieved after the anal exhaust. It is safer to leave after half an hour of rest after the examination. 2, do biopsy or polyp removal treatment patients, there may be a small amount of blood in the stool after surgery, generally no special treatment, such as bleeding more or continuous abdominal pain should be promptly to the hospital