Blood TestOffering hope for cancer patients, researchers at The Institute of Cancer Research (ICR) in the U.K. have now developed a new blood test that could predict breast cancer recurrence 8 months earlier than conventional methods such as scans. The test could provide an early warning of the disease returning after chemotherapy and surgery.

Predicting whether a breast cancer patient will relapse is a formidable challenge in modern medicine. Even when the original cancer seems to have been treated effectively, cancer cells may persist in the body and eventually grow at the original site or somewhere else in the body. This is known as a recurrence or metastasis. Recurrence rates vary among patients depending on tumor characteristics, stage of the disease, treatment received, and risk behaviors.

By monitoring patients with blood tests taken after surgery and then every 6 months in follow-up, the researchers were able to predict very accurately which patients would experience a relapse. Reporting on the ICR research findings, an article in Medical News Today says that this new test is an important step towards transforming the way cancer is monitored in the clinic and informing treatment decisions.

The test measures the level of circulating tumor DNA (ctDNA) – the DNA that has been shed by circulating tumor cells – in plasma isolated from blood, which provides a clue of the cancer returning.

The researchers examined 55 women with early-stage, early-stage, localized breast cancer before they underwent surgery, and also after they received chemotherapy. The test was repeated on each patient once every six months for a period of two years – or until they relapsed. It was found that the risk of future relapse was higher in women who had tumor DNA in their blood after being treated for early breast cancer. Of the 15 women who relapsed, 12 had circulating tumor DNA in their blood during period of the study.

One of the co-authors of the study points out that their blood test is so useful because it detects mutations only found in tumor DNA. This can help focus treatments on those who need them the most.