Scientists have developed a DNA blood test that can predict how well patients with breast cancer will respond to specific treatments, potentially allowing doctors to tailor therapy earlier and more effectively.
The test analyses circulating tumour DNA (ctDNA) released into the bloodstream by cancer cells. In a study involving 167 patients with advanced breast cancer, researchers found that low or undetectable levels of ctDNA before treatment – or after just four weeks – were strongly linked to better outcomes, including longer periods before the disease progressed and higher response rates to therapy.
The findings suggest the test could help clinicians identify early on whether a treatment is likely to work, enabling them to switch patients to alternative drugs or clinical trials sooner if needed. Researchers say the approach could reduce exposure to ineffective treatments and improve patients’ chances of controlling the disease, with further trials under way to confirm its benefits.
