Meet Cologuard: the Colon Cancer Test You Can Take at Home

Kristine Crane


Many years ago, Dan Meaney mistakenly told his doctor that his mother had died of colon cancer. In reality, she had died of uterine cancer, but the mistake led Meaney to undergo an obligatory sigmoidoscopy, a minimally invasive medical examination of the large intestine. Meaney, now 73 years old, was only 38 at the time, and says the experience was so gruesome that he vowed never to have another screening test for colorectal cancer again, despite recommendations that all adults ages 50 and up have a colonoscopy every 10 years.

Then, a few months ago, Meaney was watching "Squawk Box," a morning news and talk show, when he heard about Cologuard, an at-home, stool-based test for colorectal cancer, which the Food and Drug Administration approved last August. The insurance representative at his workplace touted Cologuard too, so Meaney decided to ask his primary care physician for a prescription to order it.

A couple weeks after taking the $500 test, which Medicare and Meaney's insurance completely covered, Meaney received a positive result. His doctor referred him for a colonoscopy, which fortunately only revealed four benign polyps. "The Cologuard gave me the proof that I needed to have a colonoscopy," Meaney says. "Anyone I've talked to about getting a colonoscopy is glad to hear about the Cologuard."

An Easier Test

Indeed, experts say a major benefit of Cologuard is its ease of use: It presents an alternative to colonoscopy that doesn't involve the two-day liquid diet many patients begrudgingly undergo to prep their bowels for examination. Experts speculate that's partly why motivating people to have colonoscopies has traditionally been like getting people to go to the dentist. The Centers for Disease Control and Prevention estimates that about 23 million people ages 50 to 75 are skipping colonoscopies.

Colon cancer is the second leading cause of cancer deaths in the U.S., and claims the lives of 50,000 Americans annually. With screening, the disease is detectable at early stages, and people diagnosed at stage I have a 93 to 95 percent survival rate -- while those diagnosed at stage IV have only a 12 percent chance of survival.

According to Eric Hargis, CEO of the advocacy group Colorectal Cancer Alliance, Cologuard is "really an opportunity to largely eliminate colon cancer in America. The more at-risk Americans screened, the more we are going to save."

But in order to reach that goal, Hargis says there must be nationwide buy-in from doctors, since they're the ones who must prescribe the test. Hargis says only 40 percent of primary care physicians recommend their patients get screened for colon cancer via traditional methods, citing a study from the American Cancer Society. "That's just a travesty," Hargis says. "Certainly patients oftentimes have to be their own advocate." The hope is that Cologuard will be enough of a game changer to begin moving that needle.

Determining the Best Test for You

Colorectal screening should begin at age 50, unless the disease runs in your family or you have symptoms such as blood in your stool or polyps. "If your doctor says you are too young for colon cancer, or tells you it's just hemorrhoids, push back," Hargis says.

Colonoscopies are recommended every decade for at-risk people or those ages 50 and up, but if you take the Cologuard test instead -- recommended every three years for 50- to 85-year-olds at average risk for colon cancer -- then you don't need a colonoscopy unless Cologuard catches something suspicious. Medicare covers Cologuard every three years, and importantly, it's the first test in history that the FDA and Centers for Medicare and Medicaid Services both approved on the same day, to accelerate availability to patients, says David Ahlquist, a professor of medicine and a gastroenterologist at the Mayo Clinic in Rochester, Minnesota.

Ahlquist, who coinvented the test, says Cologuard is as accurate as the colonoscopy in detecting 94 percent of stage I and II colon cancers, and since the test is done more frequently than colonoscopy, it could have even higher overall detection rates. The FDA cites a study comparing Cologuard to the fecal immunochemical test, or FIT, an alternative to colonoscopy patients can undergo annually to detect blood in the stool, a potential sign of cancer. In the study, Cologuard picked up cancers 92 percent of the time, compared to FIT at 74 percent. Cologuard works by detecting DNA changes characteristic of cancerous lesions or polyps, which are present in the cells lining the colon, Ahlquist explains.

While Cologuard is comparable or even better than colonoscopy at detecting precancerous and cancerous lesions, it also has a higher rate of false positives than the FIT test. According to one study, Cologuard had a 10 percent false positive rate, compared to 5 percent with FIT. But over time -- since people undergo Cologuard every three years instead of every year -- Cologuard has fewer false positives than FIT.

Another advantage of Cologuard compared to both FIT and colonoscopy is that it detects lesions on both the right and left side of colon with equal sensitivity, whereas FIT and colonoscopy detect mostly lesions on the left side, Ahlquist says. But some studies have shown an increase of tumors on the right side, making new screening methods necessary.

"If it were broadly applied across the population and was used regularly within a program, a test like this could do what PAP has done for cervical cancer, making it a rare disease," Ahlquist says. Cervical cancer used to be the No. 2 cancer killer in women, but ever since women began getting regular PAP screenings in the 1950s, rates of U.S. cervical cancer have fallen dramatically. "We're very excited by that potential scenario."


Kristine Crane is a Patient Advice reporter at U.S. News. You can follow her on Twitter, connect with her on LinkedIn or email her at kcrane@usnews.com.