Select Page

Colon Cancer Screening: Stool DNA Test

July 30, 2021

Colon cancer screening

is the cologuard stool DNA test right for me?

by Jamal Ross

Having a realization that colon cancer is a serious disease that is largely preventable is half the battle. Once you make the commitment to be tested for colon cancer, there is another challenge to determine which test is best for you.  As we continue our discussion of colon cancer tests, we will take a closer look at a test that can pick up cancer DNA in your stool. This is called a multitarget stool DNA test, but it is also known as Cologuard, which is the trade name.

The Cologuard test measures cancer DNA our stool by detecting a cancer protein called KRAS. There are other cancer proteins picked up by the Cologuard as well. This test can be performed at home, which can be seen as convenient. Yet, the Cologuard test requires a larger stool sample to be accurate in order to ensure enough cancer DNA is collected. The home testing kit comes with a bucket to collect a full stool sample and preservative to mix with your sample. The idea of collecting a larger stool sample may deter some, but there is no need to restrict your diet, take special medications or laxatives before completing this test. The Cologuard test can be done every 3 years. The Cologuard kit also contains a FIT card for you stool as well. The Cologuard test requires a prescription from you doctor. The sample needs to mailed off 72 hours after you collect your stool sample. (1) If your Cologuard test is positive, it is recommended that you receive a colonoscopy.

The Cologuard test can pick up 94% of colon cancers. (2,3) Yet, similar to the FIT, large and small pre-cancerous masses, or adenomas, are missed. Also, while the Cologuard picks up a lot of cancers, some can have a positive Cologuard test when in actuality no cancer is present. This is called a false positive result. We do not like tests that have a lot of false positive results. This leads to less accuracy and anxiety for those who end up not having cancer.

Here is the bottom line: the Cologuard test is a newer option for colon cancer screening. Unlike the FIT, Cologuard detects cancer directly. We know the test can be done every 3 years, but there is no universal agreement on this timing. While the test can be done at home, the idea of collecting and manipulating a larger sample of stool can be off-putting. While the test picks up a large number of colon cancers, it also has a problem with a number of false positive readings. All positive results need a colonoscopy. Which begs the question: Should I just start with a colonoscopy? As a result, the Cologuard test has not caught-on in the medical community and a colonoscopy remains the gold standard to detecting colon cancer.

Colon Cancer Series

Is the Stool DNA Test Right for Me?

REFERENCES
1. Doubeni C. Tests for screening for colorectal cancer. In: UpToDate, Elmore J & Lamont JT. (Eds), UpToDate, Waltham, MA. (Accessed on July 24, 2021)
2. Zauber A, Knudsen A, Rutter CM, et al. Evaluating the Benefits and Harms of Colorectal Cancer Screening Strategies: A Collaborative Modeling Approach. AHRQ Publication No. 14-05203-EF-2. Rockville, MD: Agency for Healthcare Research and Quality; October 2015.
3. Knudsen AB, Zauber AG, Rutter CM, et al. Estimation of Benefits, Burden, and Harms of Colorectal Cancer Screening Strategies: Modeling Study for the US Preventive Services Task Force. JAMA 2016; 315:2595.

Jamal Ross

Dr. Jamal Ross is an internist and pediatrician who possesses a passion for prayer and preventative medicine. He has worked in the fields of primary care and hospital medicine.

Related Posts

Colon Cancer Wrap Up and Prayer

Colon Cancer Wrap Up and Prayer

We have learned a lot in our journey to discovery more about colon cancer and some of the ways we can prevent this disease. During our colon cancer series, we learned some interesting facts about colon cancer as well as risk factors for this disease. We also learned how to make changes to our diet and lifestyle in order to lower the risk of colon cancer. We discussed colon cancer symptoms and the importance of early screening and detection. We discussed several screening methods for colon cancer and treatment options based of the stage of this disease at the time of diagnosis. Finally, we took a closer look at stage 4 colon cancer and discovered this disease is curable. Let’s review each topic in detail. Afterwards, I would like to pray for you.

Is Stage 4 Colon Cancer Curable?

Is Stage 4 Colon Cancer Curable?

We know that finding colon cancer at an early stage when it is most treatable can drastically improve survival rates. Prevention and screening are the best ways to fight colon cancer. If colon cancer is discovered when it has spread to other organs and parts of the body, this is called stage 4 metastatic colon cancer. This is the most advanced stage of colon cancer. Surgery and chemotherapy are needed to fight colon cancer at this stage. There is a sinking question: Is stage 4 colon cancer considered curable? The answer is yes! Let’s find out why.

What are the Treatments for Colon Cancer?

What are the Treatments for Colon Cancer?

If you have been diagnosed with colon cancer, it is important to know your treatment options. Some early-stage colon cancer can be treated with surgery alone without the need for chemotherapy. When colon cancer has been given time to grow, surgery and chemotherapy can be needed. The treatment course depends on the stage of your disease. There are 4 stages of colon cancer. With each stage we will discuss the treatment course. Let’s find out more about each stage of colon cancer and how it is treated.

Virtual Colonoscopy

Virtual Colonoscopy

We have discussed many options for colon cancer screening including the FIT (Fecal Immunochemical Test), Stool DNA test (Cologuard by trade name) and colonoscopy, which is considered the gold standard for detecting colon cancer. There is another option for colon cancer screening called a CT colonoscopy. Another name for CT colonoscopy is “virtual colonoscopy.” Let’s find out more about this virtual colonoscopy and whether this test is right for you.

Comments

0 Comments

Submit a Comment

Your email address will not be published. Required fields are marked *