Prosigna DNA test avoids chemotherapy

Scientists, led by University College London, have developed a DNA test called Prosigna that can identify breast cancer patients who can safely avoid chemotherapy. An international study involving over 4,000 patients over 40 in countries including the United Kingdom, Norway, Sweden, Australia, New Zealand, and Thailand, found that more than two-thirds of participants could be treated with hormone therapy alone, sparing them from chemotherapy's severe side effects. The Prosigna test measures the activity of 50 genes to assess the risk of cancer recurrence. Patients with a low score, like Karen Bonham, showed a 93.7% five-year survival rate without chemotherapy, comparable to those who received it. Professor Rob Stein, the chief investigator, emphasized this as a step towards personalized treatment. The findings, described as 'practice-changing' by Professor David Miles, will be presented at the American Society of Clinical Oncology's annual meeting in Chicago, United States. This breakthrough could allow over 5,000 United Kingdom — National Health Service patients annually to avoid chemotherapy, leading to more efficient healthcare resource utilization.