Men given just months or weeks to live after being diagnosed with prostate cancer are surviving for more than a year thanks to a breakthrough in immunotherapy treatment, a trial has shown.
Almost 40% of patients who spent 12 months on the drug pembrolizumab - known as a "checkpoint inhibitor" - as part of a new study were still alive and one in 10 had not seen the cancer grow.
The 258 men with advanced prostate cancer were treated with the drug as part of a trial led by a team at the Institute of Cancer Research (ICR) in London and the Royal Marsden NHS Foundation Trust.
The results - which are to be presented at the American Society of Clinical Oncology annual meeting in Chicago - have been lauded as "amazing".
Professor Johann de Bono, director of the drug development unit the results mark the first time immunotherapy has demonstrated benefits in men with prostate cancer, which kills more people in the UK than breast cancer.
But on this occasion, the researchers found that particular patients may benefit from such treatment depending on the genetic makeup of their tumours.
While only 5% of men in the trial saw their tumours shrink or disappear after treatment, many of those had mutations in genes involved in repairing DNA in their tumours.
Research will now focus on identifying signs to help pick out the prostate cancer patients whose tumours are most likely to shrink after the treatment.
