A 10-year study involving men with localized prostate cancer – the largest trial of its kind – has shown that a radiotherapy regimen involving higher doses of radiation is a better option than receiving lower doses. The findings also demonstrated the overall effectiveness of radiotherapy for men with localized disease.
Set up in 1998, the trial split 843 men with localized prostate cancer (meaning the cancer has not spread from the prostate gland to other areas of the body) into two groups to compare two doses of radiotherapy. Both groups also received the standard hormone-deprivation treatment alongside their radiotherapy.
After 10 years, 55% of men on the high-dose regime, compared with the 43% of men on the low-dose regimen, had survived without their disease progressing into a more hazardous form, as seen with the standard PSA test. In each half of the study, only 11% had died from prostate cancer.
The trial did not show that men given dose-escalated radiotherapy live longer, but both groups of men lived much longer than expected. Almost three quarters of all the men in the study were still alive after 10 years, and of the 236 men who had died since treatment, only 91 had died of prostate cancer.
While men who received the higher dose were more likely to have side effects associated with radiotherapy, few reported their side effects as severe. Furthermore, receiving the higher dose reduced the need for follow-up hormone treatment, which carries a risk of side effects.
Interestingly, the doses used in the study were 64 vs 74 Gy. At the Austin Center for Radiation Oncology, we’re able to use a higher dose — 81 Gy — because we implement state of the art imaging technology, such as IMRT and IGRT. These technologies allow for higher radiation doses with fewer side effects.
The key findings in this study prove that a dose-escalated regime is safe in the long term, reduces the likelihood that cancer will return and men will require further hormone deprivation treatment. If you’re currently being treated for prostate cancer, talk with your doctor to see if a dose-escalated radiotherapy regime in right for you.