On June 15, the U.S. Preventive Services Task Force (USPSTF) published its final recommendation statement(www.uspreventiveservicestaskforce.org) and evidence summary(www.uspreventiveservicestaskforce.org) on screening for colorectal cancer and found that "convincing evidence" supports screening adults ages 50-75 -- an "A" recommendation.(www.uspreventiveservicestaskforce.org)
For adults ages 76-85, the task force recommends screening on an individualized basis depending on the patient's health and previous screening history -- a "C" recommendation. Patients in this age group most likely to benefit from screening are those who
- have never been screened before,
- are healthy enough to undergo treatment if cancer is found and
- have no comorbid conditions that would significantly limit life expectancy.
"The task force strongly recommends screening adults ages 50-75 for colorectal cancer, as it reduces the risk of dying from the disease," said Albert Siu, M.D., M.S.P.H., immediate past chair of the task force in a news release.(www.uspreventiveservicestaskforce.org) "Evidence convincingly shows screening for colorectal cancer works, but not enough people are taking advantage of this highly effective service."
- The U.S. Preventive Services Task Force has issued a final recommendation statement reaffirming that screening for colorectal cancer in adults ages 50-75 reduces mortality.
- For adults ages 76-85, the task force recommends screening on an individualized basis depending on the patient's health and previous screening history.
- Both recommendations apply only to asymptomatic adults at average risk for colorectal cancer.
Both recommendations apply only to asymptomatic adults ages at average risk for colorectal cancer -- that is, they have no family history of genetic disorders linked to an increased risk of colorectal cancer (e.g., Lynch syndrome or familial adenomatous polyposis) and no personal history of inflammatory bowel disease, noncancerous growths that could lead to colorectal cancer or previous colorectal cancer.
Response to Public Comment
After a draft version of this recommendation statement was posted for public comment in October 2015, many commenters expressed concern that the terms "recommended" and "alternative" used to describe the various available testing strategies lacked clarity and were confusing.
In response, the USPSTF said it removed these terms from the final recommendation to better communicate the primary message of importance: "There is convincing evidence that screening for colorectal cancer provides substantial benefit for adults ages 50-75, and a sizable proportion of the eligible U.S. population is not taking advantage of this effective preventive health strategy."
The task force also acknowledged that for this recommendation, there isn't a "one size fits all" approach to colorectal cancer screening. As such, it sought to provide physicians and patients with the best possible evidence on the various screening methods to allow for best-informed decision-making.
Both the table and the figure included in the final recommendation statement have been updated to provide more detailed information about the available evidence on the effectiveness of each testing method, as well as the strengths and limitations of and unique considerations for the various screening tests.
Update From 2008
This final recommendation statement reaffirms the USPSTF's 2008 recommendation to screen all adults ages 50-75 for the disease. At that time, the task force recommended "against routine screening" for those ages 76-85, although it acknowledged that "there may be considerations that support colorectal cancer screening in an individual patient."
The AAFP offered similar recommendations in 2008, and it also mirrored an additional USPSTF recommendation against screening for colorectal cancer in adults older than 85. Screening for that age group has not been directly addressed in the current recommendation summary.
Comparison of Screening Protocols
Acknowledging in this latest statement that the risk-benefit profiles of available screening methods vary, the task force discussed the pros and cons of a number of protocols, such as colonoscopy screening every 10 years, annual fecal immunochemical testing (FIT) and annual high-sensitivity guaiac-based fecal occult blood testing (gFOBT).
"There are multiple screening options for colorectal cancer that reduce the risk of dying from the disease. We encourage people to choose the best option for them, in consultation with their clinician," said former USPSTF member Douglas Owens, M.D., M.S., in the news release.
In its 2008 recommendation, the task force discussed screening with flexible sigmoidoscopy every five years combined with either FIT or gFOBT every three years; the current recommendation statement specifically discusses screening with flexible sigmoidoscopy every 10 years combined with annual FIT.
These changes stem from updates in the specific strategies and estimates of test performance in the most recent Cancer Intervention and Surveillance Modeling Network (CISNET) analysis.
The USPSTF commissioned a systematic evidence review to update its 2008 screening recommendations that specifically examined
- the effectiveness or comparative effectiveness of colonoscopy, flexible sigmoidoscopy, CT colonography, gFOBT, FIT, multi-targeted stool DNA testing and methylated Septin 9 DNA testing -- either alone or in various combinations -- in reducing incidence of and mortality from colorectal cancer, as well as all-cause mortality;
- the respective harms of these screening tests; and
- the sensitivity and specificity of each test in detecting adenomatous polyps and/or advanced adenomas based on size, as well as colorectal cancer.
Unlike the 2008 evidence review, the current review expanded its search to include observational evidence about the benefits of screening tests in cases in which no trial evidence exists and comparative effectiveness studies of screening tests on cancer incidence and mortality.
In addition, the USPSTF commissioned a report from the CISNET Colorectal Cancer Working Group to provide information from comparative modeling on best age ranges and intervals for screening.
The AAFP is reviewing the USPSTF's final recommendation and the changes made since the draft version was issued in preparation for updating its own recommendation.
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