Did You Know Breastmilk Can Detect Breast Cancer Earlier?

It will come as no surprise to my readers that a person's milk provides immunity and nutrients to their baby. Many of us even share milk or donate to milk banks because breastmilk is so important for babies. But what if it could also save the mum's life?

Breast Cancer Diagnosis

Breast cancer is never a good thing to be told you have. When I was pregnant for the first time in 2013 I felt a lump in my left breast and my GP referred me straight away to get a biopsy. Because I had a breast reduction ten years earlier in 2003, I have a lot of scar tissue so it made it harder to check, so I saw an expert who did a biopsy for me and thankfully it wasn't cancer. It was an adenoma of pregnancy. I'm incredibly fortunate to have got this quickly and easily because breast cancer diagnosed during pregnancy or postpartum often has a poorer prognosis.

I have a lot of family history of breast cancer in my family, my aunt passed away from breast cancer not long after Ayla was born. A diagnosis during pregnancy is more difficult because the natural physiological changes in the breast make tumours harder to feel, and these parents are usually too young for routine mammogram screenings.

Breastmilk Can Detect Breast Cancer Earlier

Thankfully there is new ground breaking research by the Vall d'Hebron Institute of Oncology (VHIO): breast milk can now be used as a liquid biopsy to detect breast cancer earlier than conventional scans.

The Accidental Origin Story

• The Patient: Medical breakthroughs often start in the lab, but this one started with a mum's fear. A pregnant breast cancer patient, who had already been diagnosed by that point, was worried that she had passed her breast cancer to her second daughter.
  
  
• Her Concern:  Researchers assured her that passing cancer to her baby through breastfeeding wasn't possible, but she had brought some frozen breast milk in for them. It had been expressed a year before, well before her diagnosis.
  
  
• The Revelation: While cancer can't be transmitted through breast milk, researchers tested the sample anyway. Astonishingly, they found DNA with the exact mutation of her tumour in milk that had been frozen over a year before her official diagnosis.
  
  

The Science: Blood vs. Breast Milk

Liquid biopsies look for circulating tumor DNA (ctDNA) in bodily fluids. So during the study the doctors Dr. Cristina Saura and Dr. Ana Vivancos published in Cancer Discovery. They tested both blood and breast milk from patients.

In the study, ctDNA was detected in the breast milk of 13 out of 15 patients. In the blood samples taken at the exact same time, it was only found in 1 out of 15. Because the milk is produced right next to the tumor, it is a far more sensitive indicator than blood.

A New Standard of Care?

The researchers have already developed a genomic panel capable of detecting the most frequent mutations in women under 45, showing a sensitivity of over 70% and a specificity of 100%. This means that they can check our milk after we give birth and screen for cancer more effectively.

Dr. Saura gives a powerful analogy: Just as every newborn gets a heel prick test to screen for diseases, collecting a routine breast milk sample from mothers shortly after birth could become a standard, non-invasive screening tool.

Conclusion & Next Steps

• What's Next? VHIO is now expanding this into a massive trial, collecting milk samples from 5,000 healthy gestational parents globally (aged 40+ or with genetic risks like BRCA mutations) to confirm the results.
  
  
• Early detection is the ultimate key to curing breast cancer, and this non-invasive method could protect a highly sensitive population of young parents.

  
  

  Please share this article with expecting families or to click the link to read the full article from VHIO or the journal entry here. If you know a family where the mum has passed away from breast cancer with a young baby, please ask them to contact me for a pro bono memorial piece with cremation ashes and breast milk together like this ring: