Radiotherapy to the prostate in addition to standard treatment may improve survival for some men with advanced prostate cancer without detriment to quality of life, long-term study results from the STAMPEDE trial confirmed. These findings were published by Chris C. Parker, MD, and colleagues in PLOS Medicine.
Chris C. Parker, MD
Previous STAMPEDE Findings
Previous results from the STAMPEDE trial, one of the largest-ever clinical trials in the disease, showed that radiotherapy to the prostate, in addition to hormone therapy, improved survival by 11% in some men with advanced prostate cancer. On average, this may mean an extra 2 years of life compared with standard treatment. Earlier results of the trial have already led to changes in clinical guidance. New long-term findings over 5 years further support these guidelines and confirm that delivering radiotherapy to the prostate still holds benefits, even when the cancer has already metastasized.
The new findings from the radiotherapy arm of the phase III trial, led by researchers at The Institute of Cancer Research (ICR), London; The Royal Marsden NHS Foundation Trust; and the MRC Clinical Trials Unit at University College London, confirm early findings presented at the 2018 European Society for Medical Oncology (ESMO) Congress.
Long-Term Results
The long-term follow-up of the study involved around 2,000 men with advanced prostate cancer in the United Kingdom and Switzerland. Half were given standard hormonal treatment, whereas the other half received both standard treatment and radiotherapy to the prostate, the site of the primary tumor.
They found that around 65% of men with newly diagnosed prostate cancer that had spread to a few lymph nodes and bones, who were treated with additional radiotherapy, survived for at least 5 years. In comparison, 53% of men who did not receive additional radiotherapy were alive after 5 years. Similar benefits were not seen for men whose cancer had spread to many lymph nodes and bones.
The latest findings also showed that the side effects of radiotherapy were manageable, without any impact on long-term quality of life. The long-term results support current guidelines recommending prostate radiotherapy be incorporated into the standard of care, as it is a relatively inexpensive and readily available treatment option worldwide.
Commentary
Nicholas James, MBBS, PhD
Nicholas James, MBBS, PhD, Professor of Prostate and Bladder Cancer Research at the ICR and chief investigator of the STAMPEDE trial, said: “The initial 2018 findings of this arm of the STAMPEDE trial were slightly surprising. Previous thinking was that if the cancer had spread, then the horse had bolted, and there was no point in shutting the stable door by treating the original disease site. These long-term results have confirmed that this is not the case, and by treating the original site after the disease has spread, some men with prostate cancer lived longer than those on hormonal therapy alone. This could potentially benefit people with other cancers that have spread to other parts of the body, too.”
Dr. Parker, consultant clinical oncologist at The Royal Marsden and Professor of Prostate Oncology at the ICR, who led the study, commented: “These results provide further evidence that radiotherapy to the prostate extends life for some…patients whose disease has undergone minimal spread to other parts of the body. Radiotherapy is a relatively cheap, widely accessible, and well tolerated treatment, and our new data strongly support guidelines already recommending the use of prostate radiotherapy in these patients as a new standard of care, potentially benefiting many thousands of men every year worldwide.”
Disclosure: The research was also supported by the NIHR Biomedical Research Centre at The Royal Marsden and the ICR. For full disclosures of the study authors, visit journals.plos.org.
