Updated colorectal cancer screening guidelines: What to know

Today, the American Cancer Society released an update to their colorectal cancer screening guidelines. They now recommend average-risk adults begin screening for colorectal cancer at age 45 rather than age 50, as their previous guidelines stated. The lowered age for screening comes in response to scientific studies that show the rates of colorectal cancer are increasing among younger adults. We spoke with our Y. Nancy You, M.D., to learn more about the new guidelines and what they mean. How do the American Cancer Society’s new guidelines differ from current colorectal cancer screening recommendations? Why do you think they have made this change? The biggest difference with the new guidelines is that the age to start colorectal cancer screening for average-risk adults has now been lowered to 45 from 50. The guidelines also allow for a variety of screening tests, acknowledging that patient preferences and local test availability are important considerations for those being screened.  I think there are several motivations for this change. First of all, there has been strong evidence over the past few decades for an increasing colorectal cancer rates among young adults ages 18-50, especially for rectal cancers, which are more complicated to treat. There is also strong evidence these trends will continue over time. Additionally, there is a strong desire and a high level of motivation to reduce premature deaths from colorectal cancer. Almost 70% of colorectal cancers diagnosed below age 50 are already stage III or IV, meaning the cancer has spread to the lymph nodes or beyond. When diagnosed at earlier stages, current treatment options are more successful. What about individuals younger than 45? What should...