Cancer diagnoses are on the rise among young adults, particularly gastrointestinal cancers, according to new research. Americans born in 1990 face a fourfold increased risk of rectal cancer, and a twofold increased risk for colon cancer, compared to individuals born in 1950.
A recent analysis published in the British Journal of Surgery highlights that early-onset gastrointestinal cancers surged by 14.8% from 2010 to 2019. Colorectal cancer has now become the leading cancer killer for men under 50 and the second leading cause for women in the same age group. Researchers from the Dana-Farber Cancer Institute and Harvard Medical School conducted this comprehensive review.
The rise in these cancers is largely attributed to sporadic cases influenced by environmental factors rather than inherited genetic defects. Key contributors include rising obesity rates, diets high in processed foods, sedentary lifestyles, and exposures to risks that previous generations did not encounter. “The rising incidence demonstrates a birth cohort effect, implicating environmental factors, such as diet and lifestyle,” the researchers stated.
Certain demographic groups are particularly affected. For instance, over 22% of young adults diagnosed with stomach cancer are Hispanic, compared to merely 7% among older patients. Furthermore, Black, Hispanic, and indigenous populations experience disproportionately higher rates of early-onset colorectal cancer than their White counterparts.
The increase in colorectal cancer among those under 50 rose from 5.9 cases per 100,000 in 2000 to 8.4 by 2017. Notably, pancreatic cancer incidence among 25 to 29-year-olds has risen by 4.34% annually since the mid-1990s. Stomach cancer rates among women under 50 increased by 1.6% per year during the last decade, while esophageal cancer cases saw a 6.86% yearly rise among those aged 30 to 39.
This trend is not isolated to the U.S.; similar patterns are observable globally, especially in affluent nations adopting Western lifestyles. European countries have reported substantial increases in early-onset colorectal cancer, with the most alarming growth rates among those in their twenties and thirties.
Obesity is recognized as a significant risk factor, with studies suggesting that individuals with a body mass index of 30 or higher nearly double their risk of early-onset colorectal cancer. Diet plays a crucial role as well; a Western dietary pattern rich in red meat and processed foods, while low in fruits and vegetables, has been linked to these higher cancer risks. The impact of non-alcoholic fatty liver disease, affecting around 25% of adults across the globe, also notably increases the likelihood of developing gastrointestinal cancers, even in those who are not obese.
Young adults diagnosed with these cancers face unique challenges. Late diagnoses are frequent since neither patients nor healthcare providers typically expect to see cancer in someone that young, often resulting in more advanced disease stages at detection. Moreover, younger patients are subjected to more aggressive treatments compared to older individuals, despite limited evidence that such aggressive strategies statistically enhance survival outcomes.
Financial implications are considerable as well; younger cancer patients are more susceptible to acquiring what researchers term “financial toxicity,” which is intensified by hefty medical bills during peak earning years and the demands of supporting young families through treatment.
Quality of life for younger patients can also be severely impacted. Treatments like pelvic radiation for rectal cancer may affect fertility, sexual function, and bowel control, raising significant concerns for those who may have many years ahead of them.
Racial disparities in cancer outcomes are stark. Analysis of California cancer registry data reveals that Black Americans have an early-onset colorectal cancer rate of 12.2 per 100,000, compared to 9.2 for White Americans. Five-year survival rates also show a disparity, with 57.6% for Black patients versus 69.1% for non-Hispanic White patients.
In response to these alarming trends, healthcare systems are striving to adapt. The U.S. recently revised the recommended age for colorectal cancer screening from 50 to 45. However, experts caution that this reactionary measure might not comprehensively address the complexity of early-onset cases, which often exhibit distinct molecular characteristics compared to older patients.
Some recent clinical trials have shown promise, indicating that certain aggressive treatments might be safely reduced without compromising patient outcomes. Research is increasingly prioritizing the understanding of why specific birth cohorts possess higher risks, aiming to pinpoint critical exposure windows during childhood that could have lasting health impacts.
Despite medical advancements, major environmental contributors to this cancer epidemic, such as obesity and poor diet, remain unresolved. Unless significant changes occur in these lifestyle factors, the rates of rectal and other gastrointestinal cancers are likely to continue rising among a generation that faces unprecedented health challenges.
Disclaimer: This article is based on a narrative review of existing research and does not constitute medical advice. Readers should seek personalized guidance from healthcare professionals regarding cancer risk and screening.
