Start screening for colorectal cancer at age 50 years, ACP suggests

An update of ACP's 2019 guidance statement on the topic suggests that clinicians start screening for colorectal cancer in asymptomatic average-risk adults at age 50 years and consider not screening those between the ages of 45 and 49 years.

Clinicians should start screening for colorectal cancer (CRC) in asymptomatic average-risk adults at age 50 years, according to a new ACP guidance statement.

To update ACP's 2019 guidance statement on the topic, the authors searched for national guidelines from the U.S. and other countries published in English from Jan. 1, 2018, to April 24, 2023. They also searched for updates of the guidelines included in the first version of the guidance statement. The updated guidance statement is intended for all clinicians, applies to asymptomatic adult patients at average risk for CRC, and was published Aug. 1 by Annals of Internal Medicine.

The statement includes the following guidance statements:

  • Clinicians should start screening for CRC in asymptomatic average-risk adults at age 50 years.
  • Clinicians should consider not screening asymptomatic average-risk adults between the ages of 45 and 49 years. They should discuss the uncertainty around benefits and harms of screening in this population.
  • Clinicians should stop screening for CRC in asymptomatic average-risk adults older than age 75 years or in asymptomatic average-risk adults with a life expectancy of 10 years or less.
  • Clinicians should select a screening test for CRC in consultation with their patient, based on a discussion of benefits, harms, costs, availability, frequency, and patient values and preferences.
  • Clinicians should select among a fecal immunochemical or high-sensitivity guaiac fecal occult blood test every two years, colonoscopy every 10 years, or flexible sigmoidoscopy every 10 years plus a fecal immunochemical test every two years as a screening test for CRC.
  • Clinicians should not use stool DNA, CT colonography, capsule endoscopy, urine, or serum screening tests for CRC.

The guidance statement also included several clinical considerations, such as assessing patients' baseline risk for CRC (e.g., personal and family history of CRC and polyps). In addition, starting CRC screening between the ages of 50 and 60 years or screening less frequently (e.g., colonoscopy every 15 years) is likely reasonable for some adults at average risk for CRC who prefer to be screened less frequently, according to the guidance.

The guidance “shifts away from the more-testing-to-more-people approach in other U.S. guidelines,” an accompanying editorial noted. One aspect that may have deserved more attention in the guidance, however, is the advantage of colonoscopy and sigmoidoscopy screening in preventing CRC through polyp removal, in contrast with fecal tests that primarily detect and do not prevent cancer, the editorialists added.

“If they work as expected, colonoscopy and sigmoidoscopy can reduce the risk for colorectal cancer, whereas the other tests can prevent persons from dying of cancer but not from developing cancer in the first place,” they wrote. “This distinction of preventive versus early detection screening deserves emphasis in shared decision-making conversations to help patients choose the right screening option based on their preferences and needs.”