According to a reviewarticle from Mayo Clinic researchers, early onset colorectal cancer, characterized as being diagnosed when younger than 50, continues to steadily rise in the United States and other high-income countries. This increase, combined with a decrease in later-onset cases due primarily to screening, have increased the median age at diagnosis from 72 years in the early 2000s to 66 years now.
The number of younger patients with colorectal cancer at Mayo Clinic is growing, as is happening across the country. "It is important to recognize that most cases are without a known hereditary basis and have no identifiable cause," said Dr. Frank Sinicrope, the author of the study. The article was published in the New England Journal of Medicine.
"Public health measures are needed to address risk factors for colorectal cancer starting in adolescence, including poor dietary habits and physical inactivity," Dr. Sinicrope said. While the most common causes of early onset colorectal cancer remain elusive, studies show that diets with high intake of red and processed meat, as well as refined grains and processed sugar can alter gut microbial composition, resulting in chronic inflammation, increased rates of obesity, and a higher risk of colorectal cancer
"Evidence suggests that a plant-based diet and increased physical activity might help to develop a more beneficial gut microbiome, which in turn may reduce the risk of colorectal cancer," said Dr. Sinicrope.
According to the CDC, ongoing research involving large cohorts and international consortiums is to establish early life exposures that are most relevant to the development of early onset colorectal cancer.