Breast cancer ‘milk test’ good

Breast cancer is the leading cause of cancer-related mortalities among women. It can develop at any stage but the risks increase with age and obesity. A population-based screening exists for women 50 and above. Pregnant and lactating women are at higher risk but are not enrolled for population-based screening, being 45 and below.

The use of nipple aspirate fluid and ductal lavage techniques to extract aspirate for the detection of circulating breast cancer DNA is invasive and associated with adverse side effects. Additionally, the use of plasma fluid is limited as the method is only effective with metastatic, not localised, breast cancer.

Furthermore, pregnant women undergo breast tissue morphological changes, including hormonal, that impede effective clinical diagnosis of breast cancer during pregnancy. This causes pregnancy breast cancer to have delayed diagnosis and, in most cases, the condition is diagnosed when advanced.

Lactating women, too, tend to develop highly metastatic breast cancer that is also not easy to diagnose early. Given that both pregnancy and lactating breast cancers account for 55 per cent of all breast cancers, there is an urgent need for a non-invasive, sensitive and highly specific diagnosis.

A recently published study shows breast milk is not only highly sensitive and specific in detecting breast cancer-circulating DNA, but the technique can detect the tumour before metastasis and at very early stages of the tumour development, giving clinicians enough time to deploy effective treatments. And now, the droplet PCR method, a non-invasive and highly sensitive and specific test relies on the use of breast milk to diagnose breast cancer.

This new technique should go a long way in reducing breast cancer-related mortality and giving women an opportunity to seek medical intervention before the cancer becomes metastatic and advanced to a level where treatment options are expansive and with a high failure rate.

Dr Mutua is the director, ImmunoBiologic Research and Consultancy laboratory. [email protected].