Your risk of developing colorectal cancer increases as you get older. Once you hit 50, it really picks up. The vast majority of cases affect the 50 and over crowd.
But that’s now trending younger, says Amber Tierney, MD, a gastroenterologist at The Iowa Clinic’s Endoscopy Center in West Des Moines. More and more cases of colorectal cancer and the polyps that can cause it are being diagnosed in people younger than 50. This led the American Cancer Society to update its guidelines for colorectal cancer screening. Instead of starting at age 50, they now recommend that people of average risk get their first screening at 45.
Since colorectal cancer is the third most common cancer in Iowa — and the second-leading cause of cancer deaths in men — it’s important to follow the screening guidelines. And thanks to advancements in the field, you have more options than ever.
What are the different types of colorectal cancer screening?
Colonoscopy is the most well-known colon cancer test but it’s not the only one. There are a wide variety of options that fall into two categories: stool-based tests and visual exams.
Stool tests check for signs of colorectal cancer in your poop, by looking at either blood present in the sample or mutations in the DNA found in your stool. Visual exams, like colonoscopy, sigmoidoscopy and CT colonography, get a glimpse at the inside of your colon to look for the signs of colorectal cancer.
Of all these different ways to screen for colon cancer, three are the most commonly performed: fecal immunochemical tests (FIT), FIT-DNA tests and colonoscopy.
So, which one is the best screening test for colon cancer?
If you’re getting screened, you can’t go wrong — even if you have no risk factors or no symptoms. Because screening to look for the signs of colorectal cancer is the best way to prevent the disease altogether.
Each test is a little different. You can talk to your primary care provider about which one is right for you and weigh the benefits and drawbacks of the most commonly performed colon cancer screenings.
Colonoscopy
Colonoscopy is still the gold standard for colorectal cancer screening. It’s the most sensitive test available, which helps catch the disease early and more often. With a colonoscopy, a gastroenterologist can view your entire colon and rectum for signs of cancer.
“Colonoscopy is by far the best test. It’s both a screening and diagnostic procedure, so we can find and remove polyps before they turn into cancer.” Dr. Tierney says.
Many people fret over getting a colonoscopy and the bowel preparation it takes before the procedure. But it’s a very important part of the process because it’s the only way to clear out your colon to get a clear look at it. And to get the benefits of screening and diagnosis in one procedure, colonoscopy is the way to go for most people.
“Another benefit is time,” Dr. Tierney says. “If you get a colonoscopy and there are no polyps, you don’t have to worry about any screening again for 10 years.”
FIT
Along with colonoscopy, a fecal immunochemical test, or FIT, is the only other screening considered a first-tier test by the U.S. Multi-Society Task Force of Colorectal Cancer. If you decline a colonoscopy, you should get a FIT instead.
“The main benefit is that it’s a non-invasive colorectal screening test you can do at home. It’s a cheaper test, but it’s also one you have to do yearly,” Dr. Tierney says.
Fecal immunochemical tests look for hidden blood in your stool. You simply secure your sample and send it to the lab for testing. It’s more accurate and presents fewer false positives than other stool-based screenings like FIT-DNA and fecal occult blood tests.
But the lack of a visual exam is the biggest downside — and the reason you have to take a FIT annually. The test isn’t nearly as sensitive as a colonoscopy, so it fails to detect some polyps and cancers.
Cologuard Test
The most popular FIT-DNA test, Cologuard is an at-home stool test that can be ordered by your provider. Like a regular FIT, it looks for traces of blood in your poop. But Cologuard also extracts DNA from cells in your sample, which are shed from the lining in your intestines, to check for cancer or precancer abnormalities.
“It’s important to know that Cologuard is actually considered second-tier for non-invasive testing,” says Dr. Tierney. “It’s more sensitive for the detection of advanced colorectal polyps or colon cancer, but it has a lot of false positives.”
“Another thing is, Cologuard is only for low-risk patients, meaning no GI symptoms, no blood in your stool and no personal or family history of colon polyps or colorectal cancer,” she adds. “If your test is negative, then you have to repeat it every three years.”
What does a colorectal cancer screening test cost?
Nothing. There are no out-of-pocket costs.
“Something that patients don’t often realize is that insurance typically will pay for one screening exam,” Dr. Tierney says. “And these stool tests are considered screening exams.”
But while you may skip a colonoscopy initially, you may very well end up with one anyway — and have to pay for it. When a FIT or Cologuard test comes up positive, the next step is a colonoscopy. At that point, the procedure is considered diagnostic and insurance bills it differently.
“You always need a colonoscopy to make a diagnosis. You always need tissue,” Dr. Tierney says. “But the main thing is that you should be screened for colon cancer. Even if you really don’t want to do a colonoscopy, it’s much better that you take another screening test than do nothing at all.”
AmberTierney , MD
Amber Tierney, MD decided to join The Iowa Clinic because of our reputation for great patient care. She loves to develop a relationship with her patients and their families over time. When Dr. Tierney is not practicing medicine, she enjoys spending time with her two daughters.