Understanding when to start and stop screening for colorectal cancer (CRC) is imperative for early detection and avoiding delays in treatment, but also for preventing unnecessary screening. This distinction has important implications for both younger and older patients, according to data presented at DDW® 2021 by Joseph C. Anderson, MD, FACG, MHCDS, of White River Junction Veterans Administration Medical Center, and Geisel School of Medicine at Dartmouth College and The University of Connecticut Health Center.
“Many recommendations are based on randomized controlled trials, and for colorectal cancer screening, the trials have enrolled mostly people between the ages of 50 and 75,” he said. “So while those data provide good information about that age cohort, much less is known about the risk-benefit and efficacy of screening for individuals younger than 50 or older than 75.”
In determining when to initiate screening, Dr. Anderson noted a recent increase in CRC incidence in people younger than 50, with a leveling off, rather than decline in CRC-related mortality in adults 50-54 years. This suggests that people younger than 50 might benefit from early CRC screening. Moreover, younger people — especially those 45 to 49 — tend not to get diagnosed until later, when the disease is at a more advanced stage, he said.
Based on large-scale prevalence and registry data as well as models from the Cancer Intervention and Surveillance Modeling Network, the American Cancer Society (ACS) gave a qualified recommendation in 2018 for CRC screening in people at average risk (that is, no family history and no current symptoms) to begin at age 45, and the U.S. Preventative Services Task Force (USPSTF) recently changed their recommendation for screening to start at age 45. This change will have important implications for patients, providers, and public health.
“The issue of stopping screening is complicated and multifaceted,” he said. “You need to consider the comorbidity of the individual — that is, their life expectancy; whether they can endure the screening process, which can be arduous; and, if you find cancer, whether they can undergo surgery if a CRC is detected. In other words, will they benefit from screening? However, you also need to consider their risk for cancer, which is very tightly correlated with advancing age.”
For instance, when considering stopping screening, clinicians should assess:
- Whether the patient’s comorbidities allow them to benefit from having adenomas removed, if detected.
- What complications they might experience.
- Whether the patient previously screened positive for CRC.
- The patient’s preferences, because some individuals may be concerned about screening complications (such as a possible perforation).
“Now that the USPSTF changed their recommendations for 45-to-49-year-olds, we should expect reimbursement for screening in that age group to change as well,” said Dr. Anderson. “For patients 76 and older, I think that screening should be individualized based on factors discussed above.”
Dr. Anderson’s oral presentation of “When should we start and stop screening?” took place on Saturday, May 22, at 3:30 p.m. EDT, as part of the ASGE session “Colon Cancer Screening and Surveillance: Do You Know the Current Guidelines?”*
*Note: this session was recorded prior to the release of USPSTF’s new guidelines lowering the CRC screening age to 45.