Unless you have diarrhea with common enteritis, do a routine stool occult blood test and take medicine immediately. If you have frequent diarrhea or constipation or obvious bloody stool, the general doctor requires you to have a colonoscopy.
If there are polyps in the intestine, when colonoscopy must be done, the doctor will directly remove them and send them to the laboratory for testing to see if there is cancer.
Intestinal tumor markers are of little use. They are for cancer patients. It is not normal for many patients who are not sick to do this, and some of them are cancer. It is too inaccurate to do this and still show normal.
The fecal occult blood test is not 100% accurate, and sometimes it may be in the middle or late stage of the tumor.
Capsule endoscopy is expensive and the examination may be unclear, and it is impossible to extract the diseased tissue. If there is any problem, you should do ordinary colonoscopy again.
The above is for reference only. Please consult a doctor in a 3A public hospital.