The incidence of colorectal cancer has risen significantly among younger U.S. patients over the past 2 decades, according to new findings presented by Mohamed et al at Digestive Disease Week (DDW) 2024 (Abstract Mo1149) and simultaneously published in Gastroenterology.
Background
“Colorectal cancer is no longer considered just a disease of the elderly population,” explained lead study author Islam Mohamed, MD, an internal medicine resident physician at the University of Missouri-Kansas City.
Risk factors of colorectal cancer include a family history of inflammatory bowel disease or colorectal cancer. Modifiable risk factors include obesity; tobacco use; alcohol consumption; and dietary habits such as low fiber intake, consumption of processed meats or sugar-sweetened beverages, and a high-fat diet. Additionally, potential contributors to the risk of colorectal cancer include a sedentary lifestyle, the presence of bacteria that tend to cause tumors, antibiotic usage, and dietary additives; however, these factors are not firmly linked to colorectal cancer.
Study Methods and Results
In the new study, investigators used data from the U.S. Centers for Disease Control and Prevention’s Wonder Database to uncover trends in the incidence of colorectal cancer in patients aged 10 to 44 years from 1999 to 2020.
The investigators discovered that during the study period, the rate of colorectal cancer increased by 500% among patients aged 10 to 14 years, 333% among patients aged 15 to 19 years, and 185% among patients aged 20 to 24 years. In 2020, only 0.6 per 100,000 individuals aged 10 to 14 years were diagnosed with colorectal cancer compared with 0.1 per 100,000 individuals in 1999. From 1999 to 2020, colorectal cancer diagnoses increased from 0.3 to 1.3 per 100,000 individuals among patients aged 15 to 19 years and from 0.7 to 2.0 per 100,000 individuals among patients aged 20 to 24 years.
Escalations were also found in the higher age brackets, with rates rising by 71% to 6.5 per 100,000 individuals among patients aged 30 to 34 years and by 58% to 11.7 per 100,000 individuals among patients aged 35 to 39 years. While patients aged 40 to 44 years had a lower percentage increase of 37%, this group had the highest incidence rate, reaching 20 per 100,000 individuals in 2020.
The investigators reported that the most common symptoms for colorectal cancer in patients with early-onset disease were changes in bowel habits (either constipation or diarrhea), abdominal pain, rectal bleeding, and signs of iron deficiency anemia.
Conclusions
Although the number of colorectal cancer cases among patients aged 10 to 19 years was not high enough to suggest widespread colonoscopy screening, the investigators underscored that more tailored approaches may be necessary.
“It’s important that the public is aware of signs and symptoms of colorectal cancer,” Dr. Mohamed concluded.
Disclosure: For full disclosures of the study authors, visit gastrojournal.org.
