Scientists have developed a simple blood test that can predict how well patients with breast cancer will respond to treatment. The test analyses circulating tumour DNA released into the bloodstream by cancer cells and can indicate treatment success before therapy begins or after just four weeks.
Researchers studied blood samples from 167 patients with advanced breast cancer and found that low levels of tumour DNA were strongly linked to better responses and longer periods before the disease progressed. Patients with undetectable levels after four weeks of treatment had particularly positive outcomes.
The findings suggest doctors could avoid ineffective treatments and switch patients earlier to alternatives such as targeted drugs, combination therapies or clinical trials. Researchers believe the approach could lead to faster, more personalised and more effective treatment decisions, with potential benefits for both advanced and early-stage breast cancer.
