Health: When is it time for a colonoscopy?

By Dr. Burton Aronoff

If you are older than 50 it is time to think about scheduling a screening colonoscopy.

When I wrote an article a year ago, colon cancer was the leading cause of death from cancer amongst men and women and now it is the second leading cause of death from cancer. Although this is a major achievement and a major milestone, we can eliminate colon cancer as a cause of death from cancer. Most colon cancer if caught early has a cure rate of more than 90 percent, compared with those already showing symptoms having an infinitely lower cure rate. Early detection can prevent colon cancer by removing the polyps that will ultimately turn into cancer. The reason for this decrease in colon cancer is simple – two out of three patients are now being screened for colon cancer; however, one out of three are still not being screened.

Everybody thinks the early warning signs of colon cancer are change in bowel habits, blood in the stool, diarrhea, constipation, narrowing of the stool, gas, bloating, fullness, weight loss and abdominal tenderness. These are all late signs of colon cancer. There are no early warning signs of colon cancer and NO symptoms are the most frequent presentation. Patients are usually referred for anemia and tiredness. In order for early cancer to be caught at a curable stage, patients must undergo screening evaluations prior to the onset of symptoms.

The gold standard for colon cancer screening is a colonoscopy. This is a procedure done under sedation, where a tube with a very bright light is inserted into the rectum and advanced throughout the colon to evaluate every square inch of the colon. At the time of this exam, all polyps – which are benign tumors that will eventually become cancer– are generally removed. Everyone age 50 and older should be screened. Black Americans have a higher risk and should be screened at age 45 and older. Those with a family history of colon cancer or polyps should have their first exam when they are 10 years younger than their relative was when he or she developed cancer. People with ulcerative colitis and Crohn’s disease are at extremely high-risk and screening usually starts 10 years after the onset of disease and performed annually as prescribed by your gastroenterologist.

A colonoscopy is a painless examination under conscious sedation. It does require an at-home prep which used to be a gallon jug. The new preparations available include drinking two, five to six ounces of a solution followed by drinking five 12-ounce glasses of juice, soup, or whatever liquid the patient would like during the day before the procedure.

I am often asked about alternatives to a colonoscopy. The one most familiar to most patients is the Hemoccult, which is a three-day test for blood in the stool that I worked on when I was at Memorial Sloan-Kettering. This test is used by all hospitals in this state today but is not the state-of-the-art test for screening for colon cancer. The reason for this is that it picks up small amounts of blood from anywhere in the GI tract including ulcers, bleeding gums etc.

The best test today is a stool for occult blood by radio immunoassay. This new stool test picks up blood only from the colon, which is undigested and will prevent false positive exams.

There are other tests available as of October 2014 – Cologuard, which is a DNA stool analysis, was approved by the FDA and Medicare. This measures abnormal DNA from advanced polyps or early carcinoma. This test is approved every three years and only asymptomatic patients who have no prior history of colonic polyps and no evidence of pain or bleeding. This test is very suitable for patients with hereditary cancers with multiple cancers even of different type in the family known as Lynch syndrome but still needs to be followed up by a colonoscopy if positive. It is not useful in patient with colitis or other abnormalities because of false positive readings. There are many plans that do not cover this including Medicare advantage plans, Medicaid and most private insurance companies.

The gold standard is still a colonoscopy. There are capsule colonoscopies, which are quite inaccurate and usually not covered by insurance and CT: colonography, although inaccurate, still requires the same prep as a standard colonoscopy but does not require sedation; however, if any polyps are identified a standard colonoscopy will be required to remove it.

One out of three patients age 50-75 are not being screened. In a recent study, 65 percent had up-to-date screening, 7 percent had some screening and 28 percent were completely untested.

Of the unscreened patients in the study, 76 percent had insurance to cover the procedures and 24 percent did not.

Under the new Obamacare and Medicare guidelines, a colonoscopy is completely covered and there are no deductibles for preventative care. The tests including stools for occult blood, either Hemoccult or radioimmunoassay, were also completely covered again with no deductibles.

Dr. Burton Aronoff M.D. FACG is a gastroenterologist in Seaford, Delaware. He is a Fellow and governor emeritus of the American college of gastroenterology. Dr. Aronoff is on the staff of Bayhealth Milford Memorial Hospital and Beebe Healthcare in Lewes.