Stomach ulcer bacteria might also be linked to colorectal cancer

Electron micrograph of H. pylori - copy-
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CANCER DIGEST – Oct. 13, 2018 – Could a round of antibiotics prevent colorectal cancer? That’s the intriguing question coming out a new Duke University study that links the bacterium H. pylori to an increased risk of of colorectal cancers. 


The study analyzed 4,000 colorectal cancer cases and found a significant correlation between colorectal cancer and those infected with a particularly virulent strain of H. pylori that is especially common among African Americans and Asians.

Helicobacter pylori (H. pylori) is a type of bacteria that can live in the digestive tract for many years, and has been found to be the cause of ulcers, or sores in the stomach lining and upper part of the small intestine. For some people, H. pylori infection can lead to stomach cancer.

In the Duke study the researchers analyzed blood samples for H. pylori antibodies from more than 8,400 ethnically and regionally diverse study participants. Half of whom went on to develop colorectal cancer and the other half did not.

What they found was that although H. pylori infection was equally common in both groups, the infection occurred at lower rates in whites and Asians and much higher rates for blacks and Latinos.

However, among African Americans, 65 percent of the non-cancer patients had been infected while 71 percent of those with colorectal cancer had H. pylori. Similarly 74 percent of the Latinos with cancer had the infection.

That left the question, why did some people with the bacterium get cancer and others did not? The answer was in the strain of H. pylori. A particularly aggressive strain called VacA was more common in Asians and African Americans with colorectal cancer, but less common in whites and Latinos.

That leaves the researchers to study whether genetic origin or ethnic heritage plays a role in bacterial infections, and whether the presence of antibodies to H. pylori VacA could serve as a marker of colorectal cancer risk.

"The link between infection and cancer is intriguing, particularly if we can eradicate it with a simple round of antibiotics," said lead author Meira Epplein, Ph.D., co-leader of Cancer Control and Population Sciences at Duke Cancer Institute.