How can I tell if I have anal bleeding caused by colon cancer?

Judgment can be made according to the corresponding examination results, and patients are suggested to go to the hospital for consultation in time. In addition, the early symptoms of colon cancer are usually not obvious and can be easily ignored. Attention must be paid to people at high risk of colon cancer. 
Those who are over 40 years old and have one of the following manifestations belong to the high-risk group.
First-degree relatives with a history of colorectal cancer.
History of cancer or history of intestinal adenoma or polyps. 
Positive fecal occult blood test.
Colonoscopy is recommended for those at high risk with symptoms of anal bleeding. If a lesion is found under the microscope, a pathological biopsy can confirm the diagnosis.