March 7 (UPI) -- High doses of radiotherapy and hormonal therapy offer the best chance for decreasing death risk in men with aggressive prostate cancer, according to UCLA study.
The study is the first of its kind to compare radiation treatment at higher than standard doses and traditional treatments, such as radiation and the surgical removal of all or part of the prostate gland, called prostatectomy. The results were published online Tuesday in the Journal of the American Medical Association.
Researchers found the combination radiotherapy and hormonal therapy works best to prevent metastatic disease and improve overall long-term survival of men with cancers that are Gleason score of 9 or 10, the highest. The Gleason grading system assigns risk of the cancer growing.
"The type of aggressive form of prostate cancer that we focused on has sometimes been regarded as so high risk that some patients even forgo local treatments, like surgery or radiation, because they are worried that the cancer has already spread and is incurable," UCLA researcher Dr. Amar Kishan, who is an assistant professor of radiation oncology and member of the Institute of Urologic Oncology at UCLA, said a university press release.
"Our findings, in fact, show just the opposite -- in this study, the patients with the best outcomes were those who received an aggressive therapy that included so-called 'extremely dose-escalated radiotherapy' along with hormonal therapy."
Prostate cancer, the most common malignancy among men in the United States, will affect approximately 11.6 percent of men during their lifetime, according the National Cancer Institute. The number of deaths in 2017 were estimated to be 26,730.
The UCLA-led team analyzed 1,809 men treated for Gleason score 9-10 prostate cancer from 2000 to 2013 at UCLA and other sites in the United States and Europe.
In the study, 639 patients underwent radical prostatectomy, 734 had radiation and 436 underwent radiation and hormonal therapy.
Among participants with Gleason score 9-10 prostate cancer, the combination method had lower rates of prostate cancer-specific mortality and distant metastasis outcomes compared with surgery or radiation.
Patients treated with radical prostatectomy were also significantly younger than those treated with radiation or radiation and therapy, had significantly lower initial prostate-specific antigen levels and were less likely to have Gleason score 10 disease. Radical prostatectomy patients also had a significantly higher proportion of cT1-T2 lesions than the other methods.
Previous research comparing patients with radical prostatectomy to radiotherapy-based treatments have involved participants treated over multiple decades. Many were treated with lower doses of radiation and/or with insufficient hormonal therapy.