Historically most of the nations 135,000 annual cases of colorectal cancer have occurred in individuals 55 years of age and older. The current colorectal cancer screening guidelines recommend screening start at age 50 for average-risk patients which allow for the removal of polyps that over time could develop into colon cancer. This strategy appears to be working as overall the incidence of colorectal cancer in the US has been declining since the mid-1980s. This decline is thought to be primarily due to increased public awareness and colorectal cancer screening.
Embedded in this overall declining frequency of colon cancer are some alarming facts. Even though the overall incidence of colon cancer has been decreasing each year, if the numbers are broken down into age groups there appears to be a significant rise in the incidence of colorectal cancer in younger people, ages 20 to 54.
These age groups frequently referred to as Millennials (birth year 1980 to 2002) and Generation X (birth year 1965 to 1979).
Recent studies have shown a very concerning increase in the number of colorectal cancer In both the millennials and generation X ers. In 2013, 23,000 of the 135,000 cases of colorectal cancer diagnosed in the United States where patients in their 40s or early 50s. The increased incidence was even more pronounced in the millennial age group ( 20 and 30-year-olds). While the total number of colorectal cancer cases diagnosed each year in the millennials is much lower, the annual percentage increase in frequency each year was higher in this group than any other group studied.
An individual born in 1990 now has double the risk of an early colon cancer and quadruple the risk for early rectal cancer as an individual born in 1950.
Another concern is the fact that younger patients are being diagnosed at a later stage when the cancer is more difficult to treat. The delay in diagnosis is most likely because early on neither the patient or their doctor are seriously considering colorectal cancer as the cause of the patients’ symptoms.
These new findings are causing many medical organizations that publish screening guidelines, such as the American Cancer Society, to consider adjusting the current screening recommendations.
The cause of this increased incidence of colorectal cancer in younger patients is not clear. Obesity has long since been a prime suspect as the increase almost parallels the increased incidence seen with obesity. Other factors must also be in play because if it was just obesity then one would expect the rise in colon cancer to follow the rise in obesity by 10 years or more and not occur simultaneously. Poor diet, lack of activity and exercise are also thought to be involved and could also account for the simultaneous rise in both colorectal cancer and obesity.
It is important for all patients and physicians to be informed of these alarming trends and keep colorectal cancer on the list of possible causes when a patient present with compatible symptoms. Remember early detection almost always leads to better outcomes.
By James Hakert MD