Colorectal cancer is the third most common type of cancer in the U.S. It is the second leading cause of cancer related deaths within the U.S and the world.
Colon cancer is rare before age 40 and 90% of cases occur after age 50, which is why we start recommending screening for all adults at age 50. Your doctor may recommend earlier screening if you have significant risk factors, so always review your medical and family history with your doctor.
Risks for developing colon cancer include a family history, prior colon cancer, prior colon polyps, inflammatory bowel disease (not irritable bowel disease), high fat and low fiber diet, lack of physical activity, smoking, diabetes, radiation exposure, certain genetic syndromes.
Now that you’ve been appropriately warned or perhaps worried, let’s talk about ways of detecting colorectal cancer early, when it is easiest to treat.
Fecal Occult Blood Test (FOBT)
This test requires you to collect 3 separate small poop samples at home and provide them to the lab on a card, which the lab will then test for blood. This test will not be able to see the inside of your colon or detect any polyps unless they are bleeding. Because this test detects a component of blood, you do need to avoid certain foods, such as red meat prior to collecting the samples. This routine screening test is valid for 1 year only and any findings of blood will require a colonoscopy.
A colonoscopy is a medical procedure done by a trained doctor who specializes in the colon. He inserts a colonoscope, which is a long thin tube with a camera on the end, into the rectum and through the colon to visualize the tissue of your colon. Calm down, you get some medication to help you relax for this procedure and you definitely need a chauffeur as a result. Fortunately, during this procedure, if there are any polyps or areas of concern, the gastroenterologist can remove the polyp or take a biopsy immediately. Unfortunately, in order for the gastroenterologist to have a good look around, we need to give you diarrhea the day before the procedure. While it is unlikely, colonoscopy does have the risk of perforation and bleeding (when they remove the polyp).
Interestingly, the biggest complaint I get isn’t about the procedure, or even the diarrhea – it’s that the liquid to induce diarrhea tastes pretty darn icky. Even with today’s technology, the best we can do is watered down Crystal Light apparently. Sorry. For most people, this routine screening test is valid for 10 years.
A flexible sigmoidoscopy is an outpatient procedure similar to a colonoscopy that can be done by a trained doctor who doesn’t have to specialize in gastroenterology, which can increase its availability. You will still need to have bowel prep with diarrhea the day prior to get a good exam. The sigmoidoscopy does not usually use sedation and it doesn’t reach as far within the colon as the colonoscopy, which are the main differences between the two exams. A normal routine screening is valid for 5 years. If there are concerning findings on this exam, a colonoscopy will need to be completed.
Here are some possible other methods that may available, depending on your location, medical needs or the timing of your reading of this.
Double Contrast Barium Enema
A barium enema also requires the bowel prep with diarrhea. You are given a dose of barium solution rectally to outline the colon during a radiologic exam. It is less sensitive than a colonoscopy for smaller polyps and cancers. A normal routine screening is valid for 5 years. If there are concerning findings on this exam, a colonoscopy will need to be completed. We don’t usually recommend this as a routine screening for colorectal cancer.
This is a CT scan that visualizes your colon in order to look for abnormal findings. A CT scan also requires the bowel prep with diarrhea, so you still haven’t found a way to avoid that portion of the pain and suffering of maintaining your health. This screening does expose you to radiation, and the accumulation of repeated radiation may increase cancer risk in the future. A normal routine screening is valid for 5 years. If there are concerning findings on this exam, a colonoscopy will need to be completed. So far studies haven’t been conclusive on whether this screening reduces the deaths from cancer, so many insurance companies will not pay for the procedure and the USPSTF does not recommend this as a routine screening for colorectal cancer.
Immunochemical-based Fecal Occult Blood Test (iFOBT or FIT)
This newer test is more expensive than the regular FOBT. This routine screening test is valid for 1 year only and any abnormal findings will require a colonoscopy. This test is not considered effective if it is completed one time only. I haven’t known our local insurers to cover this testing, so if you find out differently, let me know.
This is a poop test which can detect both blood and DNA biomarkers that have been linked with cancerous growths. It is more expensive and new to the market so not quite ready for prime time yet. Stay tuned for more information on when this one may be incorporated into the guidelines.
The incidence of colorectal cancer in Hawaii is 43-49/100,000.
This incidence of colorectal cancer death in Hawaii is 11-14/100,000.
Let’s lower these numbers!