(HealthDay News) — While rates of colorectal cancer (CRC) have fallen among older Americans, cases among adults aged 20 to 49 are rising and expected to continue to do so, according to research published online Nov. 5 in JAMA Surgery.
Christina Bailey, M.D., of the University of Texas MD Anderson Cancer Center in Houston, and colleagues analyzed U.S. National Cancer Institute data for 393 ,241 patients diagnosed with colon or rectal cancer from 1975 through 2010. The researchers found that the overall CRC rate for Americans fell by 0.92 percent each year during that time, with a similar drop seen in men and women. Age appeared to be a factor — rates fell by 0.97 percent annually in people aged 50 to 74. However, rates rose by 1.99 percent per year among people aged 20 to 34 and by 0.41 percent annually among those aged 35 to 49.
The researchers estimate that by 2020 and 2030, colon cancer rates will increase by 37.8 and 90.0 percent, respectively, among people aged 20 to 34, but fall by 23.2 and 41.1 percent, respectively, among people older than 50.
“The increasing incidence of CRC among young adults is concerning and highlights the need to investigate potential causes and external influences such as lack of screening and behavioral factors,” the authors write.