Rectal cancer and colon cancer are collectively known as colorectal cancer, which is one of the most common malignant tumors. According to relevant information, the incidence of colorectal cancer occupies the 4th place among all malignant tumors, and there is a trend of gradual increase. The age of onset is mostly above 40 years old, and there are more men than women. The occurrence of colorectal cancer is related to chronic inflammation, colorectal polyps, adenoma and certain genetic factors. In addition, the increase of unsaturated polycyclic hydrocarbons caused by high-protein and high-fat diet increases the risk of carcinogenesis, coupled with the reduction of fiber food intake, prolonged fecal storage and accumulation of carcinogenic substances, which easily leads to colorectal cancer. Abdominal obesity and constipation are also high-risk factors of colorectal cancer. Bloody stool or mucopurulent stool, change of stool shape or habit, abdominal pain, abdominal mass, etc. are common in clinical practice. Depending on the site of occurrence, the clinical manifestation often has its own specificity. Most of the patients with colorectal cancer can get better results due to timely treatment. Therefore, we should pay attention to the following symptoms: Blood in the stool is one of the early symptoms of all colorectal cancers, but the time and nature of bleeding differs between different parts of the tumor. For rectal cancer, the amount is very small in the early stage, mostly with fresh blood marks on the side of the stool. A few patients can discharge a large amount of fresh blood after stool. In contrast, the bleeding from tumors in all segments of the colon may darken due to the longer stay in the intestine, and the color of the blood in stool may become darker to the point of discharging violet or black-purple stool, and the appearance of blood in stool is relatively late and may not be the first symptom of the patient. Often, the blood is not detectable to the naked eye due to the small amount of blood or the long retention time, and only a positive stool occult blood test is available. Changes in stool habits include changes in the timing and frequency of stools, and alternating constipation and diarrhea. Sometimes the stool is just mucus and blood, and there is a feeling of incomplete defecation. Painful defecation About 50% of rectal cancer patients have painful defecation, the degree of which may be mild or severe. Abdominal pain Some patients have vague abdominal pain as the prominent symptom, while others show paroxysmal colic with abdominal distension. Weakness, anemia and abdominal mass In the right hemicolectomy, due to the way the mass grows and the failure to detect it in time, the mass can often be palpated in the abdominal wall and systemic manifestations such as anemia are already present. Early diagnosis has a greater impact on prognosis. Regular general physical examination and necessary checkups can lead to early detection, and abnormalities such as blood in stool, stool secretion, abdominal distension and discomfort or unexplained weight loss should be promptly detected by colonoscopy, barium enema and other related examinations. Tips:Maintain a balanced diet, smooth bowel movements, good living and eating habits; regular and routine medical checkups; go to the hospital for necessary tests or consultations in a timely manner in case of blood in the stool, urination, bloating or unexplained weight loss, anemia and other abnormalities, rather than just buying some medicine and dealing with it. Colonoscopy, barium enema and other related examinations are common examinations that can be fully tolerated and should not delay the diagnosis due to excessive worries. Screening for colorectal cancer includes fecal occult blood test, colonoscopy or barium enema for people over 50 years old to start, etc.