Compared to people born in 1950, Americans born in 1990 have double the risk of colon cancer and quadruple the risk of rectal cancer. Three in 10 rectal cancer diagnoses are now for patients under 55 years old.
The risk of colorectal cancers (CRC) were lowest in 1950, but it has been on the decline since the 1980s. Still, the increased risk for younger adults puzzles scientists. Researchers, led by scientists at the American Cancer Society, poured over nearly 500,000 CRC cases between 1974 and 2013. The study was published in the Journal of the National Cancer Institute.
“Trends in young people are a bellwether for the future disease burden,” lead investigator Rebecca Siegel said in a statement. “Our finding that colorectal cancer risk for millennials has escalated back to the level of those born in the late 1800s is very sobering. Educational campaigns are needed to alert clinicians and the general public about this increase to help reduce delays in diagnosis, which are so prevalent in young people, but also to encourage healthier eating and more active lifestyles to try to reverse this trend.”
Like most cancers, the causes of CRC are not completely understood. In general, the medical research group Mayo Clinic notes that a high-fat diet, lack of exercise, diabetes, smoking and alcohol are major risk factors for CRC.
Currently, doctors usually do not screen for CRC for patients under 50 years of age. But Siegel’s study might change that standard. The Colon Cancer Alliance, an educational and support group, released a statement noting that CRC is often found too late in younger patients because doctors do not automatically screen for it.
“With five years of research studies, this is unacceptable and irresponsible,” the group’s chief executive Michael Sapienza said. “We have to do more for this generation – starting with the message to the public, to the medical community, to legislators and to everyone who will listen – that you're never too young for colorectal cancer.”