In what could be a new tool for early diagnosis of breast cancer in the postpartum period, a study has found that breast milk from breast cancer patients contains tumour DNA, and may help in early detection of the most common type of cancer affecting women worldwide.
The tumour DNA, known as circulating tumour DNA (ctDNA), can be detected through liquid biopsy in breast milk, even before breast cancer can be diagnosed using conventional imaging, as per the research published in the journal Cancer Discovery.
The findings were made by Spanish researchers at Vall d’Hebron University Hospital in Spain after a breast cancer patient diagnosed while pregnant with her third daughter raised concerns about the potential risk of her tumour being passed through her breast milk to her second daughter.
“The patient brought us a sample of breast milk that she had stored in her freezer. So, thanks to her, that’s where our project started, because although we know that breast cancer is not transmitted through breast milk, we decided to analyse the sample in search of markers that could help us in our research,” said Dr. Cristina Saura, head of the Breast Cancer Group at the university’s Institute of Oncology (VHIO).