Colorectal cancer incidence rises for the first time in two decades
A study from the University of Chicago reveals that colorectal cancer rates are increasing across all age groups up to age 69 in the United States.
Researchers at the University of Chicago have reported that the age-adjusted incidence rate of colorectal cancer rose from 36.7 per 100,000 people in 2022 to 38.3 in 2023. Published in NEJM Evidence, the findings mark the first increase in the incidence rate of the disease—the second leading cause of cancer-related deaths in the U.S.—in more than 20 years.
The sharpest rise occurred in the 45-to-49 age bracket, which saw a nearly 13% increase between 2019 and 2023. Lead author Caitlin Murphy noted that this uptick is partially attributed to the U.S. Preventive Services Task Force lowering the recommended screening age to 45 in 2021, which has resulted in earlier detection.
However, the study also identified rising rates among adults aged 65 to 69, a group with historically high screening compliance. Murphy suggested that common risk factors previously linked to early-onset cases may now be affecting older demographics, potentially offsetting the gains made through improved detection methods.
The research team is now shifting focus toward environmental chemical exposures as a potential catalyst. They plan to partner with toxicologists to analyze thousands of substances using organoids, which are laboratory-grown models capable of replicating colon tissue, to identify environmental triggers for the disease.