A blood test which helps identify cancer-specific gene mutations in the DNA could be ‘a real game changer’, researchers said Researchers from the Royal Brompton Hospital and the National Heart and Lung Institute at Imperial College London hope that it might one day be available in GP surgeries to provide a diagnosis within days and the chance of earlier treatment. The test which helps to identify cancer-specific gene mutations in the DNA could be “a real game changer” in the diagnosis and treatment for all types of cancer, according to consultant thoracic surgeon Eric Lim, who led a study on blood tests from 223 patients.