Is THIS the reason so many young people get colorectal cancer? Doctors say a FUNGUS could be to blame
Doctors may have come one step closer to revealing why colorectal cancer cases are rising among younger adults.
A mysterious rise in cases among those under 55 has raised concerns in medical circles, especially as cancer is being detected among healthy young people who “run marathons” and watch their diet.
Now, doctors at Georgetown University, in Washington DC, say the increase could be related to changes in the gut microbiomes of young people.
They found that tumors from younger patients were more likely to contain the fungus Cladosporium sp. compared to older patients.
The fungus is only occasionally found in the human intestine, where it is suspected to be an invader that does not aid digestion. The fungus is also known to cause skin and nail infections.
Scientists have come one step closer to understanding why there is an increase in cases of colorectal cancer among young people (stock)
Colorectal cancer is the third most common cancer diagnosed in the United States, according to the National Cancer Institute. And it is increasing in the young.
Approximately 153,000 Americans are diagnosed with colorectal cancer each year, of whom 19,550 are under the age of 50.
Rates in people under 55 have doubled since the 1990s, raising concern among health professionals.
A 2023 report from the American Cancer SocietyFor example, it states that the rate of colorectal cancer in Americans under the age of 55 increased from 11% of all cases in 1995 to 20% in 2019.
Dr. Benjamin Weinberg, an expert in gastrointestinal cancer, said AXIOS: ‘Many people blame obesity and diabetes.
‘But we have these patients who run marathons and eat [healthy diets] and have very advanced colorectal cancer.
For the study, the scientists looked at tissue samples from 63 patients under the age of 45 or over the age of 65.
They checked the DNA of microorganisms in the tumors to look for differences in the gut microbiome.
This revealed that Cladosporium sp. it was more frequent in tumors of young patients than in older ones.
The researchers also evaluated bacterial factors that might be at play.
There was no difference for most bacteria, such as Fusobacterium nucleatum, which was found about 30 percent of the time in both groups.
Other bacteria have also been shown to be more common in the tumors of older patients.
It is not yet clear how Cladosporium sp. could lead to this increase in cases, but the researchers believe it could damage cellular DNA. This could cause them to turn into cancer cells.
The results will be presented next week at the annual meeting of the American Society of Clinical Oncology in Chicago, Illinois.
The researchers say their paper may have brought doctors one step closer to understanding what is causing the rise in colorectal cancer cases.
Dr Weinberger added: “There was some kind of exposure that we think of in the 1970s or 1980s: maybe everyone started taking antibiotics for ear infections or stopped breastfeeding.”
“Something happened where this cohort is seeing this increase and we don’t know why.”
Previous theories have suggested that unhealthy diets, alcohol consumption and increased sedentary lifestyles could be behind the uptick.
But scientists say this doesn’t explain why other cancers have either flattened or continued to decline in those under 55 at the same time.
All tumors contain bacteria and can also contain fungi, although these are not usually present.
Part of the increase could be because people are also more likely to have colorectal cancer detected at a later stage, when it’s more difficult to treat.
A 2017 study in the journal Clinical Gastroenterology and Hepatology found that people younger than 50 tended to wait two months longer to seek care after noticing their first symptoms than people older than 50.
Amid concerns about the rising rate among younger adults, in 2021 the US Preventive Services Task Force lowered the screening age from 50 to 45 years.