Rectal finger test is the most common test for rectal diseases, mainly for the differential diagnosis of rectal cancer, and more than 80% of rectal cancers can be detected by rectal finger test. However, it is not correct to say that blood on finger test means rectal cancer, because many other diseases can also cause blood on finger test, such as rectal adenoma, polyps, internal hemorrhoids, anal fissures and ulcers, etc. Therefore, it is not scientific to say that blood on finger test means rectal cancer. The main symptoms of rectal cancer are increased frequency of stool, anal drop, pus and blood stool, etc. If there are these symptoms, further examination is needed, such as anoscopy or colonoscopy, and if there is a mass, a pathology can be taken, which can clarify what disease is causing this situation.