Consider screening average-risk adults for colorectal cancer beginning at age 45
EBM Focus - Volume 13, Issue 27
Reference: CA Cancer J Clin 2018 May 30 early online
The evidence is clear that colorectal cancer (CRC) screening among average-risk adults aged ≥ 50 years reduces disease burden. and CRC-related mortality and screening is strongly recommended by the American Cancer Society (ACS), the United States Preventive Services Task Force, and American College of Physicians. However, the ACS recently released a new qualified recommendation to initiate CRC screening at age 45 for average-risk adults. The authors cited the growing incidence of CRC in younger adults dating back to 1994. This qualified recommendation is based on two analyses of disease burden and modeling which predicted an increased number of life-years gained if screening were initiated at age 45 rather than age 50. Not surprisingly, these analyses also predicted more lifetime colonoscopies with earlier initiation of screening. Higher quality trial data demonstrating benefit or harm of initiating CRC screening at age 45 is lacking. It is worth noting, however, that expert opinion heavily influenced the somewhat arbitrary use of age 50 as the point of screening initiation in the published randomized controlled trials examining the effects of CRC screening, the data upon which the strong recommendations by many organizations are based.
The 2018 ACS guideline suggests that lowering the age of screening initiation could reduce the health disparities in populations with higher disease burden, including African Americans, Alaskan Natives, and some American Indians. Additionally, many adults delay the first CRC screening by 5 years or more, suggesting that an earlier discussion may result in higher screening rates by age 50. Certainly this line of reasoning for making a recommendation is not yet supported by a rich evidence base, but could turn out to be a valid point as more data accumulate. It is also worth keeping in mind that screening always entails risks. These include overdiagnosis (identifying cancers that never would have been symptomatic during the patient’s lifetime) and complications from invasive procedures, which in the case of colonoscopy includes a risk of serious complications of about 2.8/1,000.
Focus Point: Getting your average-risk patients to undergo CRC screening at age 50 will reduce disease burden and CRC-related mortality. In light of these new analyses, consider engaging in some shared decision-making about whether to begin screening a few years earlier in an effort to further reduce that risk.