USPSTF Updates Colorectal Cancer Screening Guidelines to Include Molecular Test

By Lori Solomon, Editor, Diagnostic Testing & Emerging Technologies

The U.S. Preventive Services Task Force (USPSTF) added molecular colorectal cancer (CRC) screening to its newly updated guidelines, but stopped short of recommending any specific screening method over the others. The guidelines, published this week in the Journal of the American Medical Association, stress the “high certainty” of benefit for colorectal cancer screening in average-risk, asymptomatic adults aged 50 to 75 years, but say that evidence does not indicate greater benefit of any one screening strategy over another. Instead, the task force stresses the importance of increasing screening rates, which remain “substantially underused,” based on patient test preference.

To inform the updated recommendations, the task force reviewed the evidence for screening with colonoscopy, flexible sigmoidoscopy, computed tomography colonography, the guaiac-based fecal occult blood test (gFOBT), the fecal immunochemical test (FIT), the multitargeted stool DNA test (FIT-DNA), and the methylated SEPT9 DNA test. The test performance, benefits, and harms of each method were evaluated. A comparative modeling study, conducted by the Cancer Intervention and Surveillance Modeling Network, provided additional information on optimal starting and stopping ages and screening intervals across the different screening methods.

The USPSTF recommends screening for colorectal cancer starting at age 50 years and continuing until age 75 years (A recommendation). The decision to screen for colorectal cancer in older adults (aged 76 to 85 years) should be an individual choice, taking into account the patient’s overall health, including comorbidities that would affect life expectancy or ability to undergo treatment, and prior screening history (C recommendation), as the benefit of screening may be more limited.

Of note, this is the first time that the USPSTF included FIT-DNA in its guidelines. The test combines a FIT with testing for altered DNA biomarkers in cells shed into the stool. This is seen as a positive for Exact Sciences, the maker of Cologuard, the only U.S. Food and Drug Administration-approved FIT-DNA test. Inclusion in the USPSTF guideline can potentially sway clinical adoption and insurance reimbursement for the test. The company’s stock price increased from $7.04 on June 14, the day the guidelines were made public to a closing price of $9.39 that day.

The draft version of the USPSTF recommendations, released in October 2015, called FIT-DNA an “alternative” strategy, which was dropped in the final guideline.

“We’re pleased with the clarity of these recommendations and expect they will expand and promote utilization of Cologuard as an innovative colon cancer screening option,” Kevin Conroy, Exact Sciences’ CEO said in a statement. “The final USPSTF recommendations … reflect the rapid evolution that occurred among cancer screening technologies during the past eight years. The recommendations offer patients a range of screening options that includes Cologuard, providing an opportunity to increase the number of people getting screened, detect more early-stage cancers, and eventually get closer to eradicating this preventable disease.”

The USPSTF acknowledged that the studies are limited to assessing test characteristics based on one-time use, making it impossible to determine the ultimate performance of a test in the real-world setting with repeated screening over time. Therefore, allowing patient preferences to shape testing strategies will hopefully lead to greater adherence to screening over time.

“Given the lack of evidence from head-to-head comparative trials that any of the screening strategies have a greater net benefit than the others, clinicians should consider engaging patients in informed decision making about the screening strategy that would most likely result in completion, with high adherence over time, taking into consideration both the patient’s preferences and local availability,” the task force concludes.

You can read more about the USPSTF CRC screening recommendations in the upcoming issue of Laboratory Industry Report.