The United States Preventative Services Task Force (USPSTF) has updated its 2008 recommendation for colorectal cancer (CRC) screening to include 7 CRC screening tests for average-risk, asymptomatic adults between the ages of 50 and 75 to reduce the risk of CRC mortality.
Colorectal cancer is the second leading cause of cancer-related deaths in the United States, with an estimated 49,000+ fatalities projected for 2016. But still, many at-risk people who should be getting screened for the disease do not.
The USPSTF’s recommendation applies to those with an average risk of developing CRC, based on characteristics of older age, male sex, and black race. Those with an increased risk for CRC, including those with an inherited known genetic disorder that leads to a high lifetime risk for CRC, and those that have had inflammatory bowel disease or previous adenomatous polyps.
Screening for adults between the ages of 76 and 85 is considered voluntary and should take into account the patient’s overall health, if they are healthy enough to undergo treatment should a cancer be detected, and prior colorectal cancer screening history.
The USPSTF also suggested that people with a positive family history for CRC be screened more frequently and starting at a younger age.
The updated recommendation reviewed the safety and efficacy of colonoscopy, flexible sigmoidoscopy, computed tomography (CT) colonography, the guaiac-based fecal occult blood test, the fecal immunochemical test (FIT), the multitargeted stool DNA test (FIT-DNA), and the methylatedSEPT9DNA test as possible methods for the detection of colorectal cancer.
“As such, the screening tests are not presented in any preferred or ranked order,” according to the recommendation statement published online inThe Journal of American Medical Association. “[R]ather, the goal is to maximize the total number of persons who are screened because that will have the largest effect on reducing colorectal cancer deaths.”
The guaiac-based fecal occult blood test should be completed on a yearly basis if the person is not in a surveillance program. According to the USPSTF’s model estimates, approximately 22 CRC deaths would be averted per every 1000 screened with this method.
FIT, which offers improved accuracy over the guaiac-based fecal occult blood test, would also be completed yearly and would prevent approximately 22 deaths per every 1000 screened.
FIT-DNA testing can be done yearly or every 3 years, according to the manufacturer. On a yearly basis, the method would prevent 23 deaths, and when completed every 3 years, the test would prevent 20 deaths. The test may result in more false-positive results but it provides increased sensitivity per single screening test than FIT.
Among the direct visualization tests, colonoscopy was suggested every 10 years. The method would avert 24 CRC deaths per every 1000 screened and would also yield the most life-years gained of all the other screening methods.
CT colonography would prevent 22 deaths when testing every 5 years.
Flexible sigmoidoscopy testing alone would avert 20 deaths when completed every 5 years. However, flexible sigmoidoscopy testing every 10 years combined with FIT every year would prevent an additional 3 deaths per every 1000 screened.
The methylatedSEPT9DNA test was found to have less than 50% sensitivity for the detection of colorectal cancer, leading to limited evidence supporting its use.
Different levels of evidence support the effectiveness of each of the screening methods. The choice for which screening test to take is up to the patient and the physician.
Benefit of Screening
Judy Yee, MD, chair of the American College of Radiology (ACR) Colon Cancer Committee, said that increased access to screening has the potential to drastically reduce the amount of deaths from CRC each year.
“If more patients come in for screening, we would be able to identify those patients with the significant precursor polyp and send them to have them removed,” Dr. Yee said in an interview withTargeted Oncology. “Additionally, if more people undergo virtual colonoscopy, we would be able to identify colorectal cancers at an earlier stage when they are more likely curable.”
Dr. Yee said that more people are still getting “traditional” colonoscopies compared with virtual colonoscopies, but with about one-third who are eligible for screening not being tested, it is clear that other options that “more appealing for patients” are needed.
Cynthia Moran, the executive vice president of Government Relations, Economics and Health Policy at ACR, said that there are a number of factors that prevent individuals from getting colonoscopies, including being uncomfortable with the sedation and invasiveness of the test.
By recommending more testing methods such as virtual colonoscopy, which is less invasive and does not require sedation, the USPSTF hopes that more people would get this potentially life-saving screening.
“About one-third of eligible adults in the United States have never been screened for colorectal cancer, and offering choice in colorectal cancer screening strategies may increase screening uptake,” according to the USPSTF statement.
Moran is confident that the new guidelines will do just that.
“Ultimately, with patient preference and implementation of coverage of non-invasive screening tests, it will result in increased screening adherence and save many lives,” she said.
US Preventive Services Task Force. Screening for Colorectal Cancer: US Preventive Services Task Force Recommendation Statement. [Published online June 15, 2016.]JAMA.doi:10.1001/jama.2016.5989.