Breast milk shows promise for early cancer detection: Spanish researchers

By Alyssa McMurtry

OVIEDO, Spain (AA) – A team of Spanish researchers have found cancer DNA in breast milk for the first time, opening the door to a revolutionary means of early breast cancer diagnosis, a study revealed on Thursday.

The research, led by two female doctors from the Barcelona Vall d’Hebron Hospital, was published in the scientific journal Cancer Discovery.

The study was sparked after a breast cancer patient brought her oncologist, Dr. Cristina Saura, a bottle of breast milk that she had frozen more than a year before her diagnosis. The patient was concerned that she might have passed cancer to her baby through the milk.

While Saura and her team knew that cancer could not be passed to the baby, she wanted to test the sample anyway. Maybe, she thought, there would be early signs of cancer in the breast milk. She was right.

After women give birth, they are at a higher risk for developing breast cancer for the next five to ten years.

"The physiological changes that occur in the breast during pregnancy and postpartum make tumors harder to detect,” Saura said in a press release from Vall d’Hebron. “Tumors in the postpartum period are more aggressive, and women are getting pregnant at ages when population screening with mammography has not yet begun.”

To test the groundbreaking discovery in hopes of being able to find a way to detect cancer earlier, Saura built a team to conduct a small study.

Of the 15 patients diagnosed with postpartum breast cancer, the team was able to detect cancer in 13 of them.

However, by analyzing the blood of the same patients, they were only able to detect cancer in one of the cases. On average, the milk detected the cancer six months before a mammogram.

Teresa was one of the participants in whom they detected cancer. She was diagnosed with the disease three months after providing her breast milk sample.

“Thanks to having detected it so early, I was operated on and had radiation treatment, but didn’t have to go through chemotherapy,” she told Spanish broadcaster TVE.

The research team’s next step is to amplify the study to 5,000 patients at risk for developing postpartum cancer. Those at risk include women who got pregnant over 40 or who have certain genes that make them more predisposed to breast cancer.

“Before this technique is implemented, we need to confirm the results in more patients,” said Saura. “But the results published today are promising and offer a potential new tool for early diagnosis of breast cancer in a particularly vulnerable population of young women and mothers. The best way to continue increasing the survival rate of breast cancer patients is to detect it as early as possible.”