With the influence of people’s lifestyle changes and other factors, the average annual number of new colorectal cancer cases in China reaches 130,000, and is increasing at an average annual rate of 4%. The latest statistics show that the proportion of colorectal cancer among young people in their 40s accounts for about 20% of the total number of colorectal cancer cases. China has entered the ranks of regions with high incidence of colorectal cancer. Colorectal cancer is one of the most common malignant tumors originating from the epithelial tissue of the colon, including colon cancer, rectal cancer and anal canal cancer. The main causes of colorectal cancer and prevention The causes of colorectal cancer are not fully understood, the main causes include: 1. 2. Precancerous lesions: such as adenoma, schistosomiasis colitis and ulcerative colitis, etc. Patients are prone to colorectal cancer. 3. Family history: If someone in the family has suffered from colorectal cancer, the risk of colorectal cancer in the immediate family is higher. How to detect colorectal cancer at an early stage? Early detection of colorectal cancer relies on reasonable screening, rather than waiting for symptoms to appear before examination. On July 8, 2011, the Centers for Disease Control and Prevention released statistics on colorectal cancer (CRC) screening and CRC incidence and mortality in the United States, which showed that screening has led to a decline in both CRC incidence and mortality in the United States. 1. General population: Screening for colorectal cancer can be started after the age of 45, and screening is performed every 5-10 years on average. 2.High-risk group: People with gastrointestinal symptoms (especially blood in stool, frequent stools, mucus stools and abdominal pain) are recommended to start screening for colorectal cancer around the age of 40, and to be examined on average once every 3-5 years. 3.People with family history of hereditary disease: We recommend to go to a large oncology center as early as possible, and through careful collection of family history by experienced clinicians and some necessary examinations, including genetic testing, to determine whether the population has hereditary tendency. If there is a genetic predisposition, the patient will be followed closely by the clinician according to a specific follow-up protocol for hereditary tumors. If there is no obvious genetic predisposition, follow-up will be conducted according to the screening program for high-risk groups. Screening means for colorectal cancer 1. Anal finger examination 2. Stool occult blood test can be used to detect a small amount of occult (latent) blood in the stool. This test is very inexpensive and does not cause any discomfort to the patient. If the test result is positive, further tests should be performed to find out the exact cause of the bleeding. 3. Colonoscopy