Liquid biopsies – the future of breast cancer detection and treatment?
January 16, 2019
Researchers are constantly trying to find quicker, more accurate and easier ways to detect breast cancer at its earliest stage. You may have heard of the liquid biopsy – using your bodily fluids, including blood or saliva, to detect cancer and to monitor its progression (even before symptoms appear). Although the liquid biopsy isn’t currently being used for the detection of breast cancer, it holds lots of potential for more effective detection and treatment in the near future. Ultimately, it could reduce the need for traditional biopsies involving taking a sample of a suspected tumour.
But, how can we determine if someone has breast cancer just by looking at their blood or saliva? Very small biological markers, including tiny traces of cancer-DNA, can actually be detected pretty early on. However, it can be hard to know which of these “biomarkers” to use – tumour DNA can change over time and patients with the same cancer can have different biomarkers. One idea is to combine a liquid and tissue biopsy. A tissue biopsy could identify unique tumour biomarkers, which could then be monitored over time using a liquid biopsy.
Liquid biopsies could also be useful after cancers have been diagnosed. For patients with advanced breast cancer, a liquid biopsy could give information on whether treatment is working and if cancer has progressed. A liquid biopsy would be more sensitive than a traditional blood test and would be a cost-effective alternative to expensive scans.
A liquid biopsy could also be used to see if your breast cancer treatment is working effectively. Response to certain drugs could be measured via your circulating tumour DNA, then treatment could be adjusted accordingly.
BCFNZ is funding Dr Parry Guilford from the University of Otago, who is currently working on a clinical trial involving 50 advanced breast cancer patients. He is monitoring patients using a liquid biopsy, which will be looking for circulating tumour DNA (ctDNA). He hopes this kind of test will allow for faster and more accurate feedback about the effectiveness of chemotherapy.
Some research scientists even believe that the liquid biopsy could be used to predict the risk of recurrence. There is currently no reliable way to predict a breast cancer recurrence. The idea would be to monitor the circulating tumour cells of women who have had breast cancer. However, substantial clinical trials over the next few years will be required to determine if a liquid biopsy could monitor recurrence.
The liquid biopsy could have the potential to improve breast cancer detection as well as making sure patients are given the right treatments. This is an exciting area of research and definitely one to keep watch of in 2019!