New Study Shows Link Between Gut Bacteria And Breast Cancer

NEW YORK (CBSNewYork) -- A surprising connection has been discovered between breast cancer and bacterium.

Even more surprising is that the bacteria may come from our gut.

As CBS2's Dr. Max Gomez reported, a new study is uncovered the unexpected link.

Felicia Harden-Bradford never thought she would get breast cancer, because she didn't have a family history.

"No-one could explain to me why I was getting cancer if I, you know, wasn't genetically set up," she said.

The same goes for Lisa Moeller; no family history and no so-called breast cancer genes, known as BRCA 1 or 2.

"I had genetic testing and I was negative for all the genetic testing," Moeller said.

Now, a new study in the journal "Oncotarget" may give a hint as to why some seemingly healthy, normal women get breast cancer.

"This is a pilot study," Dr. Charis Eng from the Cleveland Clinic said, "that looked at breast cancers and non-cancerous breast tissues. And lo and behold, there was some bacteria that were over-represented in breast cancers compared to non-cancerous breast tissues, and visa versa."

When gut bacteria, called the microbiome, get out of balance it becomes easier for disease to grow.

For the study, researchers compared the tissue of 78 breast cancer patients against breast tissue from healthy women. Healthy, non-cancerous breast tissue had more of a certain type of bacteria, but the cancerous tissues had other types of bacteria that were elevated.

The dream would be to develop a treatment like a probiotic, which would be less toxic than chemotherapy.

"Imagine if we could just give something that targets the cancer, wherever it may be, breast or otherwise," Dr. Eng said.

Since testing for breast bacteria is not at a point where that can be translated into a diagnostic test or treatment, it's important for all women to get regular mammograms -- even if you don't have a family history of breast cancer or any of the breast cancer genes.

The vast majority of breast cancers occur in women with no family history of the disease.