By David Blyweiss, M.D., Advanced Natural Wellness
December 2, 2016
- Can a stool test replace your next colonoscopy?
- At home DNA test screens for colon cancer
- Which type of testing is best for you?
If you shudder at the thought of getting your next colonoscopy, you’ll be glad to know that it may not be necessary.
That’s right. There’s a chance that you don’t have to grit your teeth every five or 10 years at the thought of starving yourself while gulping down huge quantities of liquid laxative to clear out your bowels.
Now, I’ve long been an advocate of colonoscopies. Since the early ‘90s, they’ve been the gold standard when it comes to early detection of colon cancer. This type of cancer is very slow growing. So the earlier it’s detected, the more treatable it is. As a result, colonoscopies make a great deal of sense.
But I understand why people hate them. They’re invasive and unpleasant, even scary. In fact, “Colonoscopy with biopsy or polypectomy (polyp removal) is associated with increased risk for complications. Perforation may also occur during colonoscopies without biopsies.” Serious complications occur in 0.5% of all cases. So the odds of being injured by the side effects of colonoscopy may actually be more than your odds of getting colorectal cancer in the first place.
However, it’s not the 1990’s anymore. So let’s fast-forward 46 years to today.
In recent years, fecal blood tests have become very common when it comes to screening for colon cancer. There are two types of these tests. One is the fecal immunochemical test (FIT). The other is a fecal occult blood test (FOBT).
Of the two tests, the FIT is much more sensitive when it comes to detection of early-stage cancers and relevant tumors. But FOBT isn’t far behind.
Both of these tests are able to find small amounts of blood in the stool that you can’t see with the naked eye. If blood is detected, it could be an early sign of cancer or a polyp. In this case, you would still need to follow-up with a colonoscopy.
While fecal blood tests have their uses, today’s advances in DNA have led to an even better and more accurate way to noninvasively test for colon cancer.
At Home DNA Test has High Detection Rates
Detection of blood in the stool may or may not indicate colon cancer. However, when you add DNA analysis to the equation, it can provide a more accurate picture.
This makes the latest technology on colon cancer screening, called Cologuard®, a very powerful tool.
It’s a simple test of your stool that not only detects tiny amounts of blood. It also looks for certain DNA biomarkers and genes found in colon cancer.
You see, your colon naturally sheds cells. These end up in your stool. And Cologuard® can tell whether they are abnormal or not. Abnormal genetic material in the cells could indicate cancer or pre-cancer.
Cologuard® testing catches over 92% of the cancers detected by colonoscopy. FIT, on the other hand, only catches about 73%.
Once again, however, if the results are positive, you’ll still need to undergo a colonoscopy. But if they’re negative, you might be off the hook.
All of these are reasonable alternatives if you avoid screening because you don’t want to go through the unpleasantness of a colonoscopy.
However, I do have a few warnings associated with these tests.
Which Type of Colon Cancer Screening is best for you?
Before you decide which type of test is best for you, here are three things you should know about fecal tests.
First, they can throw off false positives. This is especially true when it comes to Cologuard® testing. A false positive means that you may experience unnecessary stress and anxiety while waiting for a colonoscopy that shows no problems at all.
Second, none of them have extremely high rates of success in detecting pre-cancerous lesions. Cologuard® catches less than half as many as a colonoscopy does. FIT detects less than a quarter.
Third, these tests are not able to detect polyps which may – at some point in the future – become cancerous. When you have a colonoscopy, any polyps that are found get removed then and there.
On the other hand, they do have their advantages, especially if you’re adverse to colonoscopies.
You don’t need to go through a colon cleanse or liquid diet for these tests. Samples can be collected at home. And there’s no risk of damage to your colon. At the same time, they have relatively high detection rates.
Taking all of this into consideration, there’s absolutely no excuse to avoid colon cancer screening anymore. Considering that this is third most common type of cancer in the U.S., any one these tests could help save your life.
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