Screening for colorectal cancer (CRC) should now begin at the age of 45 and not 50 for average-risk individuals in the United States, notes the final recommendation from the U.S. Preventive Services Task Force.
The recommendation finalizes draft guidelines issued in October 2020 and mandates insurance coverage to ensure equal access to CRC screening regardless of a patient’s insurance status.
The USPSTF’s final recommendations also now align with those of the American Cancer Society, which lowered the age for initiation of CRC screening to 45 years in 2018.
“New statistics project an alarming rise in the incidence of young-onset colorectal cancer, projected to be the leading cause of cancer death in patients aged 20-49 by 2040,” commented Kimmie Ng, MD, MPH, director, Young-Onset Colorectal Cancer Center, Dana-Farber Cancer Institute, Boston, and lead author of a JAMA editorial about the new guideline.
“We must take bold steps to translate the lowered age of beginning screening into meaningful decreases in CRC incidence and mortality,” she emphasized.
The USPSTF recommendations and substantial evidence supporting them were published online May 18, 2021, in JAMA.
Risk factors for CRC
As the USPSTF authors noted, age is one of the most important risk factors for CRC, with nearly 94% of all new cases of CRC occurring in adults 45 years of age and older. Justification for the lower age of CRC screening initiation was based on simulation models showing that initiation of screening at the age of 45 was associated with an estimated additional 22-27 life-years gained, compared with starting at the age of 50.
The USPSTF continues to recommend screening for CRC in all adults aged between 50 and 75 years, lowering the age for screening to 45 years in recognition of the fact that, in 2020, 11% of colon cancers and 15% of rectal cancers occurred in patients under the age of 50.
The USPSTF also continues to conclude that there is a “small net benefit” of screening for CRC in adults aged between 76 and 85 years who have been previously screened.
However, the decision to screen patients in this age group should be based on individual risk factors for CRC, a patient’s overall health status, and personal preference. Perhaps self-evidently, adults in this age group who have never been screened for CRC are more likely to benefit from CRC screening than those who have been previously screened.
Similar to the previous guidelines released in 2016, the updated USPSTF recommendations continue to offer a menu of screening strategies, although the frequency of screening for each of the screening strategies varies. Recommended screening strategies include:
- High-sensitivity guaiac fecal occult blood test or fecal immunochemical test (FIT) every year
- Stool DNA-FIT every 1-3 years
- CT colonography every 5 years
- every 5 years
- Flexible sigmoidoscopy every 10 years plus annual FIT
- screening every 10 years
“Based on the evidence, there are many tests available that can effectively screen for colorectal cancer and the right test is the one that gets done,” USPSTF member Martha Kubik, PhD, RN, said in a statement.
“To encourage screening and help patients select the best test for them, we urge primary care clinicians to talk about the pros and cons of the various recommended options with their patients,” she added.
An accompanying review of the effectiveness, accuracy, and potential harms of CRC screening methods underscores how different screening tests have different levels of evidence demonstrating their ability to detect cancer, precursor lesions, or both, as well as their ability to reduce mortality from cancer.