Draft Screening Recommendations for Colorectal Cancer Prompt Public Comment

The US Preventive Services Task Force (USPSTF) recently posted a draft recommendation statement and draft evidence review on screening for colorectal cancer. These materials are available for review and public comment from October 6, 2015 through November 2, 2015.¹A quantitative review of the literature related to updates on screening in the form of a decision modeling study, supports the USPSTF review.²

The Proposed Screening Recommendations

The USPSTF make it clear that the patient population to whom the guidelines apply are adults ≥50 years of age, with an average risk of colorectal cancer, no family history of the disease or genetic makeup that conveys a high lifetime risk, no personal history of inflammatory bowel disease, a prior adenomatous polyp, or previous colorectal cancer. The recommendations apply to all ethnic and racial groups.²

In common with the 2008 guidelines, the USPSTF states that screening should begin at 50 years of age and continue until the age of 75 years, and is given an “A” grade rating. It recommends colonoscopy be performed every 10 years, and that there is an annual fecal immunochemical test (FIT) or high-sensitivity guaiac fecal occult blood test (gFOBT). There is a change with regard to flexible sigmoidoscopy. The 2008 version recommended screening with flexible sigmoidoscopy every 5 years together with either FIT or gFOBT every 3 years. Now the USPSTF proposes only flexible sigmoidoscopy combined with FIT, and the timing interval for the strategy has changed to flexible sigmoidoscopy every 10 years with an annual FIT.²

The USPSTF recommends against routine screening of adults from the ages of 76 to 85 years, but acknowledges patients in this age group who have never been screened may derive some benefit. This recommendation was given a “C” grade rating. They also point out that the decision to do so must take into account an individual’s health and competing risks, bearing in mind that in trials, the benefit of screening is not seen until ≥7 years later. For individuals >85 years, competing causes of mortality outweigh any screening benefit. For patients who were screened to the age of 75 years, the USPSTF recommends physicians engage in a discussion with patients about when to stop screening.²

Missing from the new proposed recommendation, but present in the 2008 version, is any rating (previously “I” grade) given to screening using computed tomographic (CT) colonography and fecal DNA testing. The proposed guidelines state that, “Screening with computed tomography (CT) colonography and multitargeted stool DNA (FIT-DNA) testing may be useful in select clinical circumstances.” For each of these two tests they state they found no studies that assessed the impact of screening on cancer incidence, morbidity, quality of life, or mortality.²

Reactions to the Proposed Recommendations

Although the USPSTF continues to recommend screening from the age of 50 years to 75 years, there is discussion concerning their lack of clear recommendation and grading of CT colonography and multitargeted stool DNA (FIT-DNA), and only an acknowledgement that these tests are potentially useful in select clinical circumstances (though not defined).²

“It is disappointing USPSTF disregarded the abundance of evidence showing that CT colonography is a better, more patient-friendly alternative to traditional optical colonoscopy, “ said Patrick Hope, executive director at Medical Imaging and Technology Alliance, in a statement. “Colon cancer screening is already dramatically underutilized, and we believe greater acceptance of CT colonography would likely increase access to early detection and life-saving treatment. It is our hope that upon review of our comments, USPSTF will endorse CT colonography for colon cancer screening.”³

In a webcast Kevin Conroy CEO Exact Science, the manufacturers of Cologuard, a stool DNA-based test, said the new proposed USPSTF language was different than what was expected. The USPSTF did acknowledge fecal DNA testing as an alternative test but it did not define those circumstances in which its use would be indicated. “We believe this will be defined in practice,” said Conroy. Stool DNA testing was rated “I” in the 2008 USPSTF recommendations and >20,000 doctors have ordered the Cologuard test and 20 payors have agreed to reimburse the test.⁴Exact Science plan to submit further data to the USPSTF by November 2^nd, which it hopes will lead to a more robust recommendation for its use. Conroy told investors that Exact Science will continue to evaluate data supporting its screening test to doctors patients, and payors and its advantages over other standard approaches.⁴

References

1. UPSTF. Public comment on draft recommendation statement and draft evidence review: screening for colorectal cancer.http://www.uspreventiveservicestaskforce.org/Announcements/News/Item/public-comment-on-draft-recommendation-statement-and-draft-evidence-review-screening-for-colorectal-cancer. Accessed October 8, 2015.

2. UPSTF. Recommendation Statement. Colorectal cancer: screening.http://www.uspreventiveservicestaskforce.org/Page/Document/draft-recommendation-statement38/colorectal-cancer-screening2. Accessed October 8, 2015.

3. MITA. MITA disappointed in USPSTF draft recommendations for colorectal cancer screening.http://www.medicalimaging.org/2015/10/06/mita-disappointed-in-uspstf-draft-recommendations-for-colorectal-cancer-screening/. Accessed October 8, 2015.

4 Exact Sciences Conference Call. October 6, 2015..http://www.exactsciences.com/about/latest-news/webcast-archive-slides-conference-call-uspstf-draft-recommendations. Accessed October 8, 2015.