Bowel cancer refers to cancer occurring in colon or rectum, and there are differences in symptom performance due to different invasion sites. Colon cancer: 1. change in bowel habits and stool characteristics: it is often the earliest symptom of rectal cancer patients, usually manifested as increased frequency of bowel movement, diarrhea, constipation, blood in stool or mucus stool; 2. abdominal pain: colon cancer patients often have persistent abdominal pain that cannot be accurately located, some patients only have abdominal discomfort or bloating, and abdominal pain will be aggravated when intestinal obstruction occurs, or manifested as paroxysmal colic; 3. 3. abdominal masses: most of the masses are hard and nodular, with a certain degree of mobility, and the general pressure pain is not obvious; 4. systemic symptoms: patients may develop systemic symptoms such as anemia, emaciation, weakness and low fever. In the late stage of disease, liver size, jaundice, edema, ascites, enlarged supraclavicular lymph nodes and cachexia may appear. Rectal cancer: 1. Rectal irritation symptoms: frequent bowel movements and change in bowel habits. The symptoms of anal cramping, urgency, and incomplete defecation may appear, and the symptoms of lower abdominal pain may appear in advanced stage patients; 2. Symptoms of cancer rupture and bleeding: blood and mucus on the surface of stool, or even pus and blood stool; 3. Symptoms of intestinal stenosis: patients with rectal cancer will have progressive thinning of stool, and when the tumor causes partial obstruction of the intestinal canal, there will be symptoms of incomplete intestinal obstruction such as abdominal distension, abdominal pain, and hyperactive bowel sounds; 4. Symptoms: As the disease progresses, rectal cancer patients may have symptoms such as frequent urination, painful urination and hematuria.