Dose-escalated radiation therapy brings mixed results in prostate cancer

Results of the study support that hypothesis. Patients who received the standard dose radiotherapy were significantly more likely to go on to salvage therapy, compared with patients in the dose-escalation arm.

Dr. Michalski and his associated reported on the randomized NRG Oncology/RTOG 0126 clinical trial, which included 1,532 patients with intermediate-risk cancer enrolled between March 2002 and August 2008 at one of 104 North American sites.

In the trial, patients with intermediate-risk prostate cancer were randomized to receive three-dimensional conformal radiation therapy or intensity-modulated radiation therapy to 79.2 Gy in 44 fractions or 70.2 Gy in 39 fractions, the study said.

With a median follow-up of 8.4 years for 1,499 patients, there was no difference in overall survival between arms, study results show. The 8-year rates of overall survival were 76% for dose-escalated radiotherapy and 75% for standard radiotherapy (hazard ratio, 1.00; 95% confidence interval, 0.83-1.20; P = .98).

Otherwise, patients in the dose-escalated radiotherapy arm had significantly lower rates of distant metastases (4% vs. 6%; P = 0.05), and lower rates of biochemical failure rates at both 5 and 8 years, investigators said.