Colon cancer is a common malignant tumor in the gastrointestinal tract, second only to stomach and esophageal cancer in incidence, and is the most common disease of colorectal cancer. It mostly occurs between 30 and 60 years old. According to clinical observation, it is found that part of intestinal cancer, which occurs on the basis of rectal polyps or schistosomiasis; some chronic inflammation of intestine can induce cancer; high fat and high protein diet causes increased secretion of bile acid, the latter is decomposed into unsaturated polycyclic hydrocarbons by anaerobic bacteria in intestine, which can also cause cancer. I. What can induce colon cancer? 1.Intestinal disorders Various acute and chronic enteritis, ulcers and polyps can cause different degrees of colonic damage and lower immunity, which can lead to malignant lesions and induce colon cancer. 2.Dietary structure Long-term high fat and low fiber intake will lay the hidden danger of colon cancer. Fat, especially animal saturated fatty acids, will increase the concentration of bile acids and cholesterol in the colon, which will produce carcinogenic substances such as 3-methylcholanthrene after metabolism, and steroid ring can also be aromatized by bacteria to form carcinogenic substances, which will accumulate in the colon. Insufficient intake of fiber leads to slow intestinal peristalsis and retention of harmful substances in the intestine, which increases the absorption of intestinal wall and increases the risk of disease. In addition, long-term consumption of pickled, smoked and barbecued foods and excessive intake of amine nitrite are very likely to induce colon cancer. 3.Heredity Clinical research shows that people with family history of the disease have a higher rate of the disease. 4.Other diseases Parasitic diseases such as schistosomiasis can lead to ulceration of intestinal mucosa, inflammation and polyps, which can cause colon cancer. What are the symptoms of colon cancer? The clinical characteristics of early colon cancer are mainly blood in stool and change of bowel habit. When the cancer is confined to rectal mucosa, blood in stool as the only early symptom accounts for 85%, but it is often not taken seriously by patients. In addition to general symptoms such as loss of appetite, weight loss and anemia, patients with middle and advanced stage bowel cancer also have symptoms of local irritation of cancer such as increased number of bowel movements, incomplete bowel movements, frequent bowel movements, and heavy weight after urgency. The enlargement of cancer may cause narrowing of intestinal cavity and intestinal obstruction. In advanced stage, colon cancer often invades the surrounding tissues and organs, such as bladder and prostate and other adjacent tissues, causing urinary frequency, urinary urgency and difficulty in urination. Invasion of the presacral plexus can cause pain in the sacrococcygeal and lumbar areas. Rectal cancer can also metastasize to the liver distantly, causing manifestations such as hepatomegaly, peritoneal effusion, jaundice, and even malignant fluid. Colon cancer is easy to be misdiagnosed. In the early stage, when there is an increase in the number of stools, mucus and pus and blood in the stool, it is easy to be misdiagnosed as dysentery, enteritis or hemorrhoids, thus losing the opportunity of early radical resection.