WEDNESDAY, Aug. 16, 2023 (HealthDay News) -- Breast, colon and pancreatic cancer rates are increasing at concerning rates among America's young adults, a new study finds.
Breast cancer accounted for the most cases in adults under 50 between 2010 and 2019, but gastrointestinal cancer rates grew fastest among the early-onset cancers studied.
Senior researcher Dr. Daniel Huang said the data suggest the need to reexamine cancer screening strategies, including the age to begin.
"Increased efforts are required to combat the risk factors for early-onset cancer, such as obesity, heavy alcohol consumption and smoking," said Huang, an assistant professor of medicine at the National University of Singapore.
Looking at data for 562,000 U.S. patients, his team found that overall early-onset cancer rates increased, particularly among women. At the same time, the cancer rate among people age 50 and older decreased.
In 2019 alone, the highest number of early-onset cases (12,649) were breast cancers. From 2010 to 2019, rates of gastrointestinal cancers were the fastest-growing among all early-onset cancers, the study found.
Gastrointestinal cancer rates among people under age 50 jumped almost 15% over the period, from 6,431 to 7,383 cases. In addition to colon cancer (nearly 2%), cancers of the appendix (15.6%), bile ducts in the liver (8%) and pancreas (2.5%) had the fastest growth rates, they noted.
"The increase in cancers among young adults has significant implications," said Hyuna Sung, senior principal scientist for cancer surveillance research at the American Cancer Society. "It is something we need to consider as a bellwether for future trends."
Why these cancers are on the rise among younger adults isn't clear, many of the risk factors hinge on lifestyle, said Sung, who wasn't part of the new study.
"Suspected risk factors may involve increasing obesity among children and young adults, also the drastic change in our diet, like increasing consumption of sugar, sweetened beverages and high fat," Sung said, also pointing to "very high" calorie intake and lack of physical activity.
She added that these trends are also being seen in other developed nations in Europe and Asia.
The study also pointed to changes in environmental exposures such as smoke and gasoline.
To take these trends into account, Sung noted that the age for colon cancer screening has already been lowered from 50 to 45. Lowering it even more probably isn't in the offing. Health officials would have to weigh the expense against the odds of finding cancer to see if it would be cost effective in terms of lives saved, she said.
For now, raising awareness among the public and health care professionals will be critical, Sung said.
"Cancer among young adults is not a common event," she said. "Overall cancer rates are substantially lower in young people. But there are these emerging trends that show the increasing rates of certain cancers among young adults."
The study noted that early-onset cancers rose 4.35% in women and dropped 4.9% in men over the study period.
Early-onset cases rose 32% among people of Asian or Pacific Island background and nearly 28% among Hispanic people over the study period. Meanwhile, rates fell almost 5% among Black Americans and 12% among white people, the study found.
Dr. John Ricci, chief of colorectal surgery at Long Island Jewish Medical Center in Great Neck, N.Y., said he and his colleagues are seeing cancers in patients in their 30s.
"We are already seeing younger patients," he said. "It's not uncommon. We used to say 40s was extremely abnormal, but we're definitely seeing more in the 30s than we had before."
Cancers of the colon and rectum are not diseases of old people, Ricci added.
"This is something that people find in their 30s and 40s," he said. "And it's a treatable disease."
The report was published online Aug. 16 in JAMA Network Open.
More information
For more on signs of cancer, see the U.S. National Cancer Institute.
SOURCES: Daniel Huang, MBBS, assistant professor, medicine, National University of Singapore; John Ricci, MD, chief, colorectal surgery, Long Island Jewish Medical Center, Great Neck, N.Y.; Hyuna Sung, PhD, senior principal scientist, cancer surveillance research, American Cancer Society; JAMA Network Open, Aug. 16, 2023, online
