Research Indicates a Sharp Increase in Colorectal Cancer Rates Among Children and Teens

Research indicates that colorectal cancer rates have notably increased among children as young as 10 over the past twenty years.

The study was presented at the Digestive Disease Week 2024 conference, and it revealed growing incidence rates of colorectal cancer in the age group of 10 to 44 from 1999 to 2020. The largest increase was observed in the age bracket of 10 to 24.

The author of the study, Islam Mohamed, MD, a resident physician of internal medicine at the University of Missouri-Kansas City, emphasizes the rising rates in younger demographics demonstrate the necessity for improved vigilance and early detection strategies for all age groups.

In recent years, a well-documented rise in colorectal cancer in young people has been observed, however, the reasons behind the trend are yet to be fully understood.

A gastrointestinal oncologist at Cleveland Clinic, Suneel Kamath, MD, confirmed that despite extensive research, it remains unclear why younger people are developing colorectal cancer more now than they were 30-40 years ago.

Experts believe the new study underlines the urgent need for further research to determine the contributing factors to this sharp increase in colorectal cancer among children, teenagers and young adults.

Kamath debunked the myth that there is such a thing as being too young to get cancer and stressed the importance of vigilance for cancer even in younger individuals. According to Kamath, additional funding is needed to study our environment, diet and lifestyle in a bid to identify other carcinogens resulting in this escalating early-onset colorectal cancer rate.

Despite colorectal cancer being most prevalent among older adults, the documented increase in cases in younger individuals prompted Mohamed and his team to further examine the incidence patterns in the U.S.

The research team used data from the Centers for Disease Control and Prevention (CDC) Wonder database, which includes public data on mortality, cancer incidence, census data, vaccinations and more. They scrutinized colorectal cancer incidence rates among seven different age groups from 10 to 44 between 1999 and 2020.

The team discovered that rates had increased in all age groups during this time, with a sharper increase observed among younger demographics.

Despite the steepest percentage increases being in those aged 10 to 24, it's worth noting that those who are middle-aged and older were still more likely to develop colorectal cancer. This age group's incidence rate rose, albeit at a slower rate.

For instance, about 14.6 in 100,000 people aged 40-44 developed colorectal cancer in 1999, but by 2020, the ratio increased to 20 in 100,000. For the 15-19 age group, incidence went from 0.3 in 100,000 to 1.3 in 100,000 during the same period.

While research continues to figure out why incidence of colorectal cancer is on the rise, the known risk factors are assumed to be similar across both older and younger populations. These risk factors include obesity, a diet high in processed foods and red meats, a sedentary lifestyle, heavy drinking and smoking, Kamath explained.

Hina Saeed, MD, deputy director of radiation oncology at the Lynn Cancer Institute at Boca Raton Regional Hospital, who was not involved in the study, asserts that the acknowledged risk factors for colorectal cancer can't completely explain the rising incidence in individuals under 45. Environmental factors and certain genetic conditions such as Lynch syndrome or a family history of colorectal cancer could be contributing factors.

Kamath points out that while it's worrisome that cases of colorectal cancer have been steadily increasing among young individuals for the past 20 to 30 years, the frequency is not yet high enough to recommend widespread screening. He suggests several measures can be taken including investing in research on the risk factors among young people and increasing public awareness about the disease.

“We can educate the public—and the medical community, especially those in primary care—that symptoms like blood in the stool, constipation that goes on for months, thin stools, [and] unexplained weight loss should be investigated with a colonoscopy, even in young people,” Kamath said.

Though guidelines recommend people start getting colonoscopies at age 45, having more open conversations about colorectal cancer can help people figure out if they need to start getting screened at a younger age, Kamath added.

Because so many people shy away from sharing information related to their colorectal health, there’s a good chance that a significant amount of people should be getting early colorectal cancer screenings, but don't know it.

“I don’t think most people share with their family members that they have had polyps removed, [and] many people don’t share with their family that they had cancer,” Kamath said. “The reality is more of the population is high-risk for cancer and needs screening than we even realize. There are a lot of people that we could screen sooner and prevent these early-onset cancers.”

The ways in which doctors address colorectal cancer risk in young people need to be modified, Saeed said. But experts aren't quite sure what this looks like just yet.

“The rising rates of colorectal cancer among young people [suggest] that colorectal cancer is not just a disease of older adults,” she explained. “Strategies for prevention, treatment, and survivorship may need to be tailored for younger populations.”