These microscopic specks of blood can signal colorectal cancer or precancerous polyps. When faithfully conducted every one to two years, the FOBT reduced the incidence of colorectal cancer because patients with positive results underwent another, more sensitive test to determine the source of the blood, according to the new study. Most colon cancers begin as benign polyps, so throughout the trial, doctors removed non-cancerous polyps they found via colonoscopy.
Colon cancer develops and grows slowly.
The polyps whether cancerous, benign or on their way to becoming cancerous bleed only intermittently. Regular fecal occult-blood testing is essential because it increases the odds of catching the polyp while bleeding. Unless the patient is at increased risk for developing colorectal cancer, testing should begin at age 50, and a digital rectal exam should be done at the time of each flexible sigmoidoscopy, colonoscopy or barium enema examination. Some people may find these screening tests uncomfortable or embarrassing. But putting up with a little discomfort or embarrassment can save lives.