Scientists find new gut virus linked to colorectal cancer that could lead to earlier diagnosis

Scientists have discovered a new virus found in common gut bacteria that is linked to colorectal cancer.

It’s not yet clear whether the virus helps to actually cause the cancer or if it’s simply a sign that something in the gut has changed, but researchers at the University of Southern Denmark say the colorectal cancer patients they studied were more likely to have the virus than others without the cancer.

The scientists believe the findings could help to improve colorectal cancer screening, and tests for the virus could potentially lead to earlier detection, though more studies need to be done before those tests could be created.

Still, detecting colorectal cancer early is crucial, as that can dramatically improve patients’ survival rates and allow doctors to remove precancerous growths before they become harmful.

Colorectal cancer is expected to result in 55,230 deaths in the U.S. this year, according to the American Cancer Society, and is the second-most common form of cancer for both men and women.

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The research started with Bacteroides fragilis, a bacterium that scientists have examined for years.

It’s the most common cause of anaerobic infections in humans, according to the National Institutes of Health, but is also found in people who never develop cancer.

“It has been a paradox that we repeatedly find the same bacterium in connection with colorectal cancer, while at the same time it is a completely normal part of the gut in healthy people,” Dr. Flemming Damgaard said in a statement.

Damgaard and the team decided to look at whether there are differences within the bacterium.

They looked at data from two million Danish patients and singled out those who had experienced a serious bloodstream infection caused by the bacterium.

Several of those patients were diagnosed with colorectal cancer within just weeks.

The researchers analyzed the bacterium’s genetic material in patients with and without cancer, which is how they first found that bacteria from cancer patients were more often infected with specific viruses.

Next, they analyzed stool samples from nearly 900 people in the U.S., Europe and Asia, finding that those with colorectal cancer were approximately twice as likely to have traces of these viruses in their gut, including the previously undescribed virus.

“The number and diversity of bacteria in the gut is enormous. Previously, it has been like looking for a needle in a haystack. Instead, we have investigated whether something inside the bacteria – namely viruses – might help explain the difference,” said Damgaard.

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Damgaard is working to examine how gut tissue, the bacterium and the virus interact, as well as looking for it within colorectal cancer tumors and seeing if mice genetically predisposed to develop cancer get it more quickly with the virus in their gut.

While it’s too soon to create tests for the virus, preliminary analysis showed the virus could identify around 40 percent of cancer cases, the researchers said.

“In the short term, we can investigate whether the virus can be used to identify individuals at increased risk,” said Damgaard.

Colorectal cancer is detected primarily through cancer screening, including stool and blood tests, biopsies and colonoscopies.

The disease disproportionately affects men. While it is still most frequently diagnosed in people over 50, rates of colorectal cancer are rising in younger adults, partially due to the lowering of the recommended age for screening to 45.

Dawson’s Creek star James Van Der Beek died of colorectal cancer earlier this month at age 48.

Doctors are still working to understand why and what exactly triggers the disease, but have suggested gut health could be an important factor, as well as genetics, diet and lifestyle.