Atrium Health Gastro & Hepatology gastroenterologist Dr. Brittany Seminara is convinced the very best way to detect and prevent colorectal cancer is with a colonoscopy. She makes her case as she compares and contrasts the colonoscopy with other screening options, the Cologuard and virtual colonoscopy also known as CT-colonography. The colonoscopy is the very best strategy, she asserts.

Your Health, News | 7 months ago

Easier Than You Think, a Colonoscopy is Your Best Prevention of Colon Cancer

Atrium Health Gastro & Hepatology gastroenterologist Dr. Brittany Seminara is convinced the very best way to detect and prevent colorectal cancer is with a colonoscopy. She makes her case as she compares and contrasts the colonoscopy with other screening options, the Cologuard and virtual colonoscopy also known as CT-colonography. The colonoscopy is the very best strategy, she asserts.

“Don’t sell yourself short,” says Brittany Seminara, MD, a gastroenterologist at Atrium Health Gastroenterology and Hepatology. “We are doing ourselves and our families a disservice if we do not take the time to take care of ourselves and our colon.”

Dr. Seminara isn’t holding back because colon cancer is the third leading cause of cancer death for both men and women in America, but it’s also one of the few we can actually cure with early detection and even prevent with the removal of precancerous polyps.

Colorectal cancer is the third most diagnosed cancer in both men and women in America, according to the American Cancer Society (ACS). They estimate in 2020 there will be 104,610 new cases of colon cancer and 43,340 new cases of rectal cancer in the United States alone. But the ACS’ further numbers tell an even bigger story because the death rate from colorectal cancer is dropping mainly because precancerous colon polyps (abnormal tissue growths) are being found and removed in time before they can develop into cancer. One million Americans have defied colorectal cancer because of early detection and prevention.

What’s the best strategy for you? 

Colonoscopy is the most widely recognized screening tool and is the gold standard when it comes to detection and prevention. Dr. Seminara and the ACS recommend that people at average risk of colorectal cancer begin screening colonoscopies starting at age 45.

But there are important misconceptions to address. As far as screening, there are three ways you can go, says Dr. Seminara, and there are pros and cons to each however  there is a clear winner in her mind:

1. The Cologuard Test

What it is: It’s a mail-in stool sample kit that’s made available for patients as an alternative to in-office procedures. This FDA-approved test screens for colon cancer by identifying abnormal fecal DNA and blood that is shed by cancer as well as high-risk colon polyps.

Convenient but lacking: The biggest value for the Cologuard is convenience, you can do it home and there is no prep involved. However, Dr. Seminara cautions that while Cologuard is very good detecting colon cancer (92% sensitive) it is not as good in detecting high-risk colon polyps (42-64% sensitive). It can also lead to more expense in the long run because if the test is positive then you will need a colonoscopy to find and remove these polyps, this colonoscopy may not be covered by insurance since it is no longer screening (as the Cologuard was the screening test) now it is diagnostic.

What is a colon polyp? A colon polyp is a lesion or small clump of cells that forms on the lining of the colon. We know that most colorectal cancers start as a polyp, others start from chronic inflammation. They are easily found as they look like small lumps or even mushrooms on a stalk. However, there are more flat carpet-like polyps that can spread along the colon wall, which can make them more difficult to detect with conventional imagining studies. 

Another downside is that Cologuard can miss advanced polyps, which can lead to a false sense of security after a negative screening test. False positives are also common and require follow-up colonoscopy that could have accurately detected results from the start.

Dr. Seminara is especially concerned about flat polyps. “We know flat polyps can be more aggressive, and they also have characteristics that make them more difficult to identify even in a colonoscopy, which is why technology has advanced to allow the majority of gastroenterologists to use high-definition scope, which is the only kind of scope we use here at Atrium Health,” she says. “Since we know the Cologuard test can miss high-risk polyps, again, why risk it? Patients are given false confidence since the Cologuard results are considered good for three years when there could be a polyp changing in that time (missed in this type of screening). We don’t yet know what in the body tells a polyp to change and become cancerous. The best way is to identify and remove and that can only be done via colonoscopy.”

2. Virtual Colonoscopy (or CT Colonography)

What it is: It’s is an imaging procedure, which displays two- and three-dimensional digital images of the colon for a radiologist to review.

A better idea, but doesn't give the full picture: “Well,” Dr. Seminara begins, “you get an actual picture with a colonography, we’re not just looking at fecal DNA or blood as you are with the Cologuard. That’s better for detection, but not prevention. The patient still has to clean out the colon with colon prep, the colon needs inflated with a contrast while the patient is awake during the CT scan so it is not exactly “noninvasive.” then a radiologist has to then interpret the images before you know the results. The radiologist will detect most polyps, but they may miss some, especially small or those high-risk flat polyps. So, if you have to go through the prep (which is a cause of apprehension for colonoscopy) then colonoscopy is a bigger bang for your buck, to me.”

Also, it’s important to consider how long these tests will cover you before it’s time to reevaluate your colon again. A negative Cologuard only gives you a three-year clearance, the colonography gives you a five-year clearance, and the colonoscopy gives you a ten-year clearance.

3. Colonoscopy

What it is: It’s an examination of the colon using a thin endoscope (a flexible tube with a camera and ports for water, air and instruments used for  biopsy or polyp removal). 

The best choice: Dr. Seminara is a clear advocate for the colonoscopy, for detection, preventative care and treatment, however she recognizes some of the concerns:

  • Will it be uncomfortable? Anesthesia is typically given for this procedure to improve discomfort however there are various levels of anesthesia offered. “It’s ultimately the patient’s decision though, what they are most comfortable with, anywhere from no sedation to monitored anesthesia care with the use of propofol. This is something you have the right to discuss with your doctor so everyone is on the same page of your wants and needs to make sure you are comfortable,” Dr. Seminara says. “There’s no pain maybe some discomfort and some people can experience some spot bleeding, but most patients feel fine immediately after the procedure. Depending on the level of sedation, “some go right back to work,” she adds, “as long as the doctor says it’s okay but if sedation was given it is best to take the day off and return to work the next day”
  • Is the prep that bad? Not at all but you do have to consume a drink provided by your doctor, called the colon prep, that will trigger your bowel to clear itself out in order to have a thorough exam. Advances have been made in this area as well, there are many options from large quantity “flushes” to smaller quantity preps that you will drink it the night before or day of the procedure along with a liquid diet. Those flat polyps, especially, require a clear sight. Dr. Seminara says this, too, is something to discuss with your doctor. “The prep is definitely getting better. Newer preps offer a smaller, only around 50 ounces in quantity compared to 4 L in the past. There is talk in industry about a prep pill in the future, but we are not quite there yet. That just shows that we are listening to our patients and interested in making as tolerable as possible. I get questions about what you can drink with the prep and as long as you do not mix it with anything red, drink it with the liquid of your choice, drink it cold or through a straw that helps. Again, talk about your concerns with your doctor. Come up with a plan that suits you best.”
  • Will there be bloating after the procedure? Water or air is required to inflate the colon for improved visibility. We now CO2 instead of ambient air which can leave you colon faster or using more water can help decrease bloating. Seminara has a technique she uses to prevent this that only adds a few more minutes and gives her a second look for those hard-to-find polyps. “Once I go in, I can go back to suck the air out. Ask your doctor about what can be done to help limit discomfort after. 

The colonoscopy is the best solution

“This is about cancer detection and cancer prevention,” Dr. Seminara says. “The Cologuard and colonography have a place in some circumstances. But, removing potentially premalignant polyps to prevent cancer is what I want to do as your doctor, what I’m sure you want your doctor to do, too. The best choice is cancer detection and prevention, and only the colonoscopy can do that.”