European Society for Radiotherapy and Oncology (ESTRO) May 17 2026 Treating breast cancer that has begun to spread around the body with targeted radiotherapy could help patients to live longer without their cancer getting worse, according to the results of a small randomised controlled trial presented at the Congress of the European Society for Radiotherapy and Oncology (ESTRO 2026). Once cancer has begun to spread within the body (metastasise) it generally becomes harder to treat and survival