Colon tumors are tumors occurring in the colon, including ascending colon, transverse colon, descending colon and sigmoid colon, and their clinical symptoms are as follows: 1. change in stool habit: it is the most common symptom of colon tumors, mainly manifested as increased number of stools or constipation; 2. change in stool properties: manifested as unformed stools, thin stools, and some patients may have blood in stool; 3. abdominal pain and bloating; 4. colon secondary to inflammatory bowel disease In patients with tumor, symptoms of inflammatory bowel disease may appear before the onset. Once the above symptoms appear, you should go to hospital for colonoscopy in time for clear diagnosis and symptomatic treatment.