A blood test may be able to save lives of several cancer patients by finding tumors that have again started to grow in a patient’s body even after treatment. A team of scientists at the Institute of Cancer Research in London said they were able to find traces of breast cancer eight months before doctors would normally have noticed.

Scientists said during the first trail, the test found that 12 cancers out of 15 women who relapsed. The other three patients all had cancers that had spread to the brain where the protective blood-brain barrier could have stopped the fragments of the cancer entering the bloodstream.

Experts said there was still some way to go before there was a test that could be used in hospitals i.e. surgery in which doctors removed tumor.

However, as per the team a tumor starts from a single cancerous cell and if part of a tumor has already spread to another part of the body or the surgeon did not remove it all then there are higher chances of cancer to make a return.

Scientists of the study published in Science Translational Medicine followed 55 patients who were at high risk of relapse because of the size of the tumor. The scientists analyzed the mutated DNA of the tumor and then continued to search the blood for those mutations.

None of the women in the study were told that cancerous material had been detected as it would have been unethical to base decisions on such an unproven prototype, said scientists.

Dr Nicholas Turner, one of the researchers, said, “The key question is are we identifying that these women are at risk of relapse early enough that we could give treatments that could prevent the relapse?”