Initial results of a European phase III trial (SAKK 09/10), reported in the Journal of Clinical Oncology by Ghadjar et al of the Swiss Group for Clinical Cancer Research, showed little difference in acute toxicity with salvage radiotherapy of 70 vs 64 Gy in patients with biochemical recurrence of prostate cancer after prostatectomy.1 Quality-of-life analysis showed greater worsening of urinary symptoms in the dose-intensified group. Pirus Ghadjar, MD, of Charité Universitätsmedizin Berlin, Germany, is the corresponding author of the Journal of Clinical Oncology article.
In the trial, 344 patients without evidence of residual disease from sites in Switzerland, Germany, and Belgium were randomized between February 2011 and April 2014 to receive radiotherapy at 70 Gy/35 fractions (n = 175) or 64 Gy/32 fraction (n = 169) using three-dimensional conformal radiation therapy or intensity-modulated radiation therapy/rotational techniques. The primary endpoint was freedom from biochemical failure. Secondary endpoints included acute toxicity and quality of life assessed at up to 3 months after treatment. Quality of life was assessed by the European Organisation for Research and Treatment of Cancer (EORTC) Quality-of-Life Questionnaire (QLQ) C30 and the prostate cancer module QLQ-PR25; urinary symptom score (QLQ-PR25) was the primary quality-of-life endpoint.
Toxicity and Quality of Life
Acute grade 2 and 3 genitourinary toxicity was observed in 16.6% and 1.7% of the 70-Gy group vs 13.0% and 0.6% of the 64-Gy group (P = .2). Acute grade 2 and 3 gastrointestinal toxicity was observed in 15.4% and 2.3% vs 16.0% and 0.6% (P = .8).
Early changes in quality of life were minor. Patients receiving 70 Gy had a greater and clinically relevant worsening in urinary symptoms (P = .02).
The investigators concluded: “Dose-intensified [salvage radiation therapy] was associated with low rates of acute grade 2 and 3 [genitourinary and gastrointestinal] toxicity. The impact of dose-intensified [salvage radiation therapy] on quality of life was minor, except for a significantly greater worsening in urinary symptoms.” ■
Disclosure: The study was supported by grants from the Hedy and Werner Berger-Janser Foundation; Swiss Cancer Research Foundation; Radio-Onkologie Berner Oberland AG Switzerland; and Swiss State Secretariat for Education, Research, and Innovation. For full disclosures of the study authors, visit www.jco.ascopubs.org.