Researchers reported on Tuesday that rates of colorectal and other gastrointestinal cancers are increasing among Americans younger than 50. They might have an explanation: the growing prevalence of obesity in the U.S. seems linked to a higher risk of developing these cancers early in life. A significant study from 2019 indicated that women classified as obese had almost double the chance of suffering from early-onset colorectal cancer. It’s anticipated that nearly half of all U.S. adults could be obese by 2030, according to research from the same year.
Obesity is known to cause inflammation and elevated insulin levels, which contribute to cancer risks, including various gastrointestinal cancers, according to the Centers for Disease Control and Prevention. Other contributing factors may include smoking, alcohol consumption, a diet typical of Western lifestyles, and non-alcoholic fatty liver disease.
Earlier this year, new findings highlighted the effects of a gut toxin called colibactin, which can damage DNA in colon cells, potentially leading to cancer. This toxin is produced by E. coli bacteria, often associated with foodborne illnesses.
At this point, the exact cause of the increase remains uncertain, but it’s clear that this trend is not confined to the U.S.
“The incidence of GI cancers in adults younger than 50 is rising globally,” stated Dr. Sara Char, an oncology fellow at Boston’s Dana-Farber Cancer Institute.
Gastrointestinal Cancer Rates in the U.S.
In the U.S., there has been a noticeable rise in early-onset cases among both men and women since the mid-1990s. When comparing adults born in 1950 to those born in 1990, the latter face double the risk of colon cancer and four times the risk of rectal cancer, according to researchers.
Moreover, early-onset colorectal cancer has become the leading cause of cancer-related deaths for men under 50 in America, while it ranks second for women in the same age group. Colorectal cancer, being the most prevalent type of gastrointestinal cancer, notably affects Black, Hispanic, Indigenous, and Asian populations disproportionately.
Changing Treatment Approaches
These alarming findings imply a potential need to rethink treatment practices, as researchers pointed out. Patients diagnosed with early-onset colorectal cancers often face diagnostic delays since neither healthcare providers nor patients typically expect cancer at such young ages. When diagnosed, these patients frequently have advanced disease, which can lead to more aggressive treatments that might not always improve survival outcomes.
Colorectal cancer holds the position of the third leading cause of cancer-related deaths among men in the U.S. and fourth among women. The disease is the second most common cause of cancer deaths overall, with predictions suggesting around 52,900 deaths this year, according to the American Cancer Society.
The researchers emphasized that younger patients might face greater financial burdens due to their diagnosis, along with issues related to body image, mental health, and overall quality of life.
“Ongoing research into the biology of early-onset GI cancers is crucial for developing more effective screening, prevention, and treatment options,” Char, the lead author of the study, explained.
This research was published by Oxford University Press in the journal BJS.
