You are using an older browser version. Please use a supported version for the best MSN experience.

There's a new blood test to screen for colon cancer. So should you skip the colonoscopy?

USA TODAY logo USA TODAY 3/28/2019 Stephanie Innes

No. 60: Sonora Quest Laboratories | Medical laboratories| 2018 Arizona employees: 3,100 | 2017 Arizona employees: 3,100 | Ownership: Public/non-profit | Headquarters: Phoenix © David Wallace/The Republic No. 60: Sonora Quest Laboratories | Medical laboratories| 2018 Arizona employees: 3,100 | 2017 Arizona employees: 3,100 | Ownership: Public/non-profit | Headquarters: Phoenix PHOENIX – An Arizona company has a new colon cancer blood test on the market that sounds like an enticing alternative to the oft-dreaded colonoscopy.

The $170 blood test, called BeScreened-CRC, was developed by Phoenix-based diagnostics laboratory Beacon Biomedical and is a screening tool for colon cancer, its developer says.

Sonora Quest Laboratories in Arizona has offered the test since December, and no doctor's order is required. It's not covered by Medicare. Coverage by commercial insurance plans varies.

The BeScreened-CRC blood test was developed for a "very specific audience," said Don Weber, CEO of Beacon Biomedical, and it is not a substitute for a colonoscopy.

"It's really geared towards the individuals who are either unwilling or unable to follow the current recommended screening guidelines, such as fecal-based testing or colonoscopy," Weber said. "Colorectal cancer is the most preventable cancer because it's probably the slowest growing cancer out there."

More: Marcia Cross spoke out about diagnosis to 'put a dent in the stigma around anal cancer'

Early-stage colon cancer has a 90 percent five-year survival rate. If the cancer has spread to distant parts of the body, however, the five-year survival rate is 14 percent, the American Society of Clinical Oncology says.

Yet more than one-third of Arizonans are still skipping recommended colon cancer screenings, whether it's because of fear, squeamishness or other reasons. 

The rate of uninsured Arizonans getting recommended screenings for colon cancer is even lower – only 30 percent, according to the most recently available research from the National Cancer Control Program and the CDC

For most adults, the risk factor for colon cancer is older age. The median age at diagnosis is 68. Colon cancer causes about 49,000 deaths per year in the United States.

However, the prevalence of colon cancer among younger, working-age people has recently increased. As a result, the American Cancer Society just last year lowered the recommended age for starting colon cancer screenings for people of average risk, from 50 to 45.

The U.S. Preventive Services Task Force, an influential government-appointed panel of disease prevention experts, is in the midst of updating its colon cancer screening recommendations. The most current set, published in 2016, recommends that screenings begin at the age of 50 and continue through age 75. That age range could change when the recommendations are updated.

"We'll be trying to figure out what the evidence says is the best thing for patients and clinicians to do," said task force vice chair Dr. Alex Krist, who is a professor of family medicine at Virginia Commonwealth University.  

The new colon cancer blood test is not approved by the FDA yet

Phoenix colon and rectal surgeon Dr. Anathea Powell says she's not familiar with the BeScreened-CRC blood test, though the concept is good because it's convenient, she said.

"We need to make sure that it is as efficacious as the standard screenings," said Powell, who works with the University of Arizona Cancer Center at Dignity Health/St. Joseph’s Hospital and Medical Center.  

Patients may order a BeScreened-CRC blood test through Sonora Quest Laboratories – an Arizona-based joint venture between Banner Health and Quest Diagnostics – and get their result via an online portal. If the test is negative, then no further action is needed. If it's positive, then patients are told to see their physician for follow-up testing, likely a colonoscopy, Weber said.

Developers of the test say it was created in accordance with federal standards for laboratory testing, and that its own clinical study showed a 94 percent accuracy rate.

The test is not approved by the U.S. Food and Drug Administration. Beacon Biomedical officials say they plan to seek FDA approval, and they emphasize approval is not required for a clinical test. 

More: Start colon cancer screening at 45, not 50, American Cancer Society urges

Another blood test already exists to screen for colorectal cancer called methylated SEPT9 DNA, which measures genetic variants in plasma to detect cancer. The $380 test has been approved by the FDA and unlike BeScreened-CRC, it requires a doctor's order. This blood test has never been evaluated against BeScreened-CRC, Weber of Beacon Biomedical said.

The methylated SEPT9 DNA test is not included in the list of colon cancer screening tests recommended by the U.S. Preventive Services Task Force because of limited evidence on its effectiveness.

The approved, validated colon cancer testing methods right now are either stool testing or visual, via a colonoscopy, or virtual colonoscopy, Powell said. Another visual screening method is flexible sigmoidoscopy, but it's seldom used in mainstream medicine.

"Unfortunately I am not as familiar with the blood testing right now," Powell said. "Our preference is the colonoscopy, with the understanding that it can be difficult, particularly for patients who cannot miss work, and who may not have any sick time, those sorts of things."

'A more robust study' is needed, one gastroenterologist says of blood test

Dr. Suryakanth R. Gurudu, a gastroenterologist at Mayo Clinic in Arizona who researches colon cancer prevention, said he's not familiar enough with the BeScreened-CRC to say whether it's effective, though the idea of a blood test is promising. He did note that the company's stated 94 percent accuracy rate is backed up with a study of 110 people, which is not a very large sample.

"They need to have a more robust study using thousands of patients, to say if this is good for Stage One cancer detection as well," Gurudu said. "If you don't, then it's an inferior quality screening test."

The test measures three protein markers that Weber says indicates the presence or absence of colorectal cancer. The company recommends it for people ages 50 through 85. 

The company's information for physicians does not mention precancerous lesions, said Gurudu, who reviewed the test's online marketing materials at the request of The Arizona Republic, but was otherwise unfamiliar with it.

"With a colonoscopy we detect polyps, before they even turn into colon cancer." Gurudu said. 

Many medical experts agree colonoscopies are the "gold standard" for colon screening. It allows removal of precancerous lesions, or polyps, at the same time and only needs to be done every 10 years if no polyps are found.

"It's very satisfying for me that if I scope someone, I can take care of the problem right there and prevent a problem down the line," Powell said. 

But colonoscopies do have a negative side. An aggressive laxative bowel preparation, usually taken the day before the procedure, causes diarrhea, which can impede activities like being at work. The procedure itself will require the day off work, and the patient will need someone to drive them home since the colonoscopy requires sedation.

"The risk we worry about with a colonoscopy is perforation. But it's a low risk, about 0.3 percent or so, but still not zero," Powell said.

Stool testing is another alternative to colonoscopy, but has an 'ick' factor

While a colonoscopy may be the gold standard, if people are skipping them, the take-home stool tests are an acceptable alternative for average-risk patients who have no personal or family history of colon cancer or of any related cancers, Powell said. 

It is more convenient, less expensive than a colonoscopy, and has no procedural risk.

"I definitely think stool testing has a place for patients who are going to be very concerned about a colonoscopy," or who may not have easy access to one, Powell said.

There are three different stool tests available to patients – a fecal occult blood test (FOBT), fecal immunochemical test (FIT), and a FIT-DNA test often referred to as the stool DNA test. Cologuard is the only FIT-DNA test that is FDA-approved.

Exact Sciences Corp. says it has sold 2 million of the Cologuard tests since 2014. Cologuard requires a doctor's prescription and is covered by Medicare, Medicare Advantage and some private insurance companies. For people paying cash, the list price is $649.

Powell said of the three, her patients most frequently use the FIT test, which uses antibodies to detect blood in the stool, is recommended annually, and costs about $26. Powell finds the FOBT to be less reliable, and the FIT-DNA test is not affordable for some of her patients.

FIT-DNA testing combines the FIT testing with testing for DNA shed by tumors, and  it's recommended every three years – less often than the FIT test. The test is highly sensitive, there's a chance of a positive result even though there isn't really a problem, Powell said.

One downside to the take-home stool testing seems to be the "ick" factor. Officials with Sonora Quest Laboratories say only one-quarter of the patients who get an at-home stool testing kit from them actually return a sample – a key reason they are offering the blood test.

Any screening is better than no screening, Powell and Gurudu concurred.

"Detecting cancer that has already metastasized has very poor prognosis compared to Stage One cancer," Gurudu said. 

Follow Stephanie Innes on Twitter: @stephanieinnes.

This article originally appeared on Arizona Republic: There's a new blood test to screen for colon cancer. So should you skip the colonoscopy?

UP NEXT
UP NEXT

AdChoices
AdChoices

More From USA TODAY

image beaconimage beaconimage beacon