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Screening for colorectal cancer (CRC) should begin at age 45 for all average-risk adults in the United States, the .

Screening should continue at recommended intervals until age 75, the draft states. For patients ages 76 to 85, the decision to continue screening should be based on an individualized assessment of the benefits and harms associated with screening.

"Colorectal cancer screening saves lives," according to a statement from the USPSTF. "For the first time, the Task Force is now able to recommend that all adults ages 45 to 75 be screened to reduce their risk of dying from this disease."

The draft recommendations lowers the age for initiation of screening from 50 to 45 but otherwise are consistent with the 2016 USPSTF recommendations. The change was made in response to recent evidence that the incidence of CRC is increasing in people younger than 50. The also recommends that CRC screening begin at age 45 for average-risk individuals. The recommends age 50 as the starting age for average-risk adults and 45 for Blacks.

According to the USPSTF statement, the screening recommendation for patients ages 50 to 75 is based on A-level evidence (high certainty of net benefit), typically randomized, controlled trials. The recommendation to lower the starting age for screening to age 45 is based on B-level evidence (moderate certainty of net benefit, usually cohort and observational studies).

The recommendation for individualized decision-making at age 76 is based on expert opinion (C-level evidence). Patients in this age group are more likely to benefit if they have never been screened for CRC.

Although CRC remains the third leading cause of cancer death in the U.S., about a fourth of adults ages 50 to 75 have never been screened for the disease.

"Unfortunately not enough people in the U.S. receive this effective service that has been proven to save lives," Task Force chair Alex Krist, MD, of Virginia Commonwealth University in Richmond, said in the statement. "We hope that this recommendation to screen people ages 45 to 75 for colorectal cancer will encourage more screening and reduce people's risk of dying from this disease."

Recent evidence showing increased rates of CRC in younger individuals influenced the decision to lower the age for initial screening to 45. The recommendation will be especially beneficial for Blacks, who are more likely to die of CRC.

"Screening earlier will help prevent more people from dying from colorectal cancer," said USPSTF member Michael Barry, MD, of Massachusetts General Hospital in Boston.

The draft recommendations support different types of screening strategies, including stool-based tests and direct visualization of the colon. Serum- and urine-based tests and capsule endoscopy were not included because of limited evidence.

Among stool-based screening strategies, the Task Force recommends high-sensitivity guaiac fecal occult blood testing (HSgFOBT), fecal immunochemical testing (FIT), and stool DNA (sDNA) testing. The only stool DNA test currently available incorporates a FIT component.

According to the USPSTF, current evidence suggests that annual screening with FIT or sDNA-FIT results in greater life-years gained as compared with annual HSgFOBT or sDNA-FIT every 3 years. Annual screening with sDNA-FIT would lead to more colonoscopy procedures as compared with annual FIT.

Some uncertainty exists regarding the accuracy of HSgFOBT to detect CRC and advanced adenomas. However, the accuracy likely is lower than that of other stool-based screening strategies and is more difficult for patients to use, the Task Force members stated.

Among the three recommended options for direct visualization, colonoscopy and computed tomography (CT) colonography allow visualization of the entire colon and the rectum, whereas visualization with flexible sigmoidoscopy is limited to the rectum, sigmoid colon, and descending colon.

The Task Force cited evidence that screening colonoscopy every 10 years or CT colonography every 5 years results in more life-years gained as compared with flexible sigmoidoscopy every 5 years.

"We urge primary care clinicians to discuss the pros and cons of the various recommended options with their patients to help decide which test is best for each person," said Task Force member Martha Kubik, PhD, RN, of George Mason University School of Nursing in Fairfax, Virginia.

The draft recommendations are available on the . The recommendations are open to until Nov. 23.

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