How Accurate Are Home Screenings for Colorectal Cancer?

CRC screenings

There has been recent media coverage regarding people who received a medical co-payment fee from a colonoscopy performed after having a positive Cologuard® test. We've provided a few links to the report, which appeared in a number of publications:


A matter not reported in the article is that a large quantity of these test results can be false-positive, prompting people to worry about having polyps or cancer and being faced with a potential medical co-pay even when receiving a negative colonoscopy result.

One recent study involving 450 individuals, exhibited at Digestive Disease Week in May 2021, revealed that only two percent of individuals with a positive stool test had colon cancer. Moreover, two-thirds of the individuals received a false-positive result, which may have generated more out-of-pocket costs for a colonoscopy to confirm the results of the home test, as described by the media reports. Furthermore, many health insurance plans will provide benefits for a simple colonoscopy that detects and minimizes the chance of colon and rectal cancer as a preventive service.

Facts about colon and rectal cancer

Colon cancer, or cancer of the large intestine, causes the death of more than 50,000 lives every year. It is the second most common type of cancer fatality in the U.S. Colorectal cancer can be prevented, treated, and overcome, but only when detected accurately and early on. Because this cancer commonly arises as growths, or polyps, in the lining of the colon (large intestine), identifying and removing these growths is the most effective option to guard against colon cancer.

There are three main methods of screening for colorectal cancer:

  1. Colonoscopy – 95% of large colon polyps are identified
  2. Stool DNA (Cologuard testing) – 42% of large colon polyps are detected
  3. Fecal Immunochemical Test (FIT) – 30% of large colorectal polyps are discovered

Colonoscopy exams are regarded as the gold standard for finding polyps in the colon. Polyps detected throughout the course of a colonoscopy test are removed during the process, often eliminating the requirement for additional procedures.

In the event that potential polyps are detected through a Cologuard or positive FIT test, a colonoscopy will have to be performed to eliminate the intestinal growths. Bigger growths could remain undetected with FIT and Cologuard tests. When polyps fail to be identified and removed, the risk of developing colon cancer increases significantly.

Recently, the U.S. Preventive Services Task Force (USPSTF) recommended that screenings for colorectal cancer begin at age 45 vs. 50. As a result, an additional 22 million adults age 45 – 49 should be assessed for colon cancer this year. While home colorectal cancer screening tests may appear to be a more accessible, cost-effective process, it is essential to realize that a colonoscopy is the only screening method that has the ability to identify and protect against colon and rectal cancer.

Detecting vs. preventing colon cancer

Home colon cancer screenings (such as Cologuard) are intended to discover cancerous markers (DNA) in the fecal specimen provided. But in 58% of cases, dangerous precancerous growths aren't discovered at all with Cologuard kits. A screening test, like Cologuard, should be completed every 36 months if initial test results provide a negative outcome. Cologuard has a history of providing a substantial amount of false-positive and false-negative outcomes. In a recent survey, two-thirds of the participants who completed the Cologuard at-home test had false-positive results. A positive test outcome from the blood or stool screening requires that a colonoscopy be performed to confirm the outcomes. Since the blood or fecal test is deemed to be a "screening" assessment, the subsequent colonoscopy is regarded as a "diagnostic" colonoscopy.

Colonoscopies are examinations that serve to identify and protect against colon and rectal cancer. They detect over 95% of harmful, precancerous polyps, which are excised at the time of the procedure. A colonoscopy can also permit the biopsy of tissue for pathological testing to discover (with greater precision) if colorectal cancer is present. As a result, colonoscopy procedures are much more conclusive and provide preventive measures since they remove any precancerous polyps or abnormal cells identified in the large intestine.

The predominant specifications of colonoscopy procedures include:

Screening/preventive colonoscopies are carried out most often for asymptomatic patients (those with no previous or current intestinal issues) age 45 or older who wish to undergo a baseline screening to learn if they could be at early risk for colorectal cancer. This type of colonoscopy permits the doctor to identify any abnormal areas in the large intestine, such as growths and abnormal cells. Throughout the course of a screening colonoscopy, polyps (which can turn cancerous) can be eliminated and tissue samples can be performed to discover if malignant cells are occurring in the colon. A preventive colonoscopy is advised every ten years for patients without symptoms between the ages of 45 – 75 who carry no personal or family history of gastrointestinal diseases, colon polyps, or colon cancer. A large number of insurance carriers typically offer benefits for screening colonoscopies when performed for preventive reasons. It is important to consult with the insurance provider prior to having a colonoscopy to understand what is covered and whether there may be any out-of-pocket fees associated with the procedure.

Surveillance colonoscopies are performed if an individual has a history of GI disease, colon polyps, or cancer but may be asymptomatic (having no GI symptoms in the present or past). The requirement of a surveillance colonoscopy can range according to the individual's personal history. Patients who have experienced colon polyps in the past would receive a surveillance colonoscopy and most likely have further surveillance exams every 2 – 5 years or so. It is important to check with the insurance provider ahead of undergoing any colonoscopy to determine coverage amounts and any estimated out-of-pocket expenses.

Follow-up/diagnostic colonoscopies are recommended if a person develops or has previously experienced polyps, GI symptoms, anemias, or a GI diagnosis or disease. A person's health history and outcomes from any prior colonoscopy screening(s) determine the recommendation for a diagnostic colonoscopy. For example, if an individual undergoes a non-invasive colon cancer screening test, such as FIT or Cologuard, that generates any kind of positive result, a follow-up colonoscopy is generally required to verify the results of the screening evaluation. Follow-up colonoscopy procedures often require out-of-pocket payments, making it vital to speak with the insurance provider before having the procedure to gain an understanding of coverage amounts and any potential out-of-pocket costs.

For patients who are 45 years of age or older, it is important to have a colorectal cancer screening as a baseline and preventive measure to facilitate lasting colon health. It is also crucial to realize the disparities between colorectal cancer screening options and how each type works. Colonoscopy continues to be the most effective exam for detecting cancer and the sole form of colon cancer prevention available.

Hear more about colon and rectal cancer screenings in New Orleans, LA

If you have further concerns surrounding home colorectal cancer screenings or want to arrange for a colonoscopy, please contact Metropolitan Gastroenterology Associates. Our New Orleans, LA gastrointestinal experts are ready to provide the help you need for long-term digestive health and wellness. Colon cancer screenings are simple examinations that can save your life. Contact our caring team today to learn more.