Role of Post-Prostatectomy Radiation Clarified
Greatest benefit in prostate cancer patients who have positive surgical margins on prostatectomy
THURSDAY, Sept. 27 (HealthDay News) -- Immediate postoperative radiotherapy following prostatectomy appears beneficial in improving disease-free survival in patients with positive, but not negative, surgical margins, according to study findings published in the Sept. 20 issue of the Journal of Clinical Oncology.
Theodorus H. Van der Kwast, M.D., Ph.D., of the University Health Network in Toronto, Canada, and colleagues reviewed prostatectomy specimens from half of the participants of the European Organisation for Research and Treatment of Cancer (EORTC) trial to identify factors that predicted benefit from adjuvant radiotherapy. The trial had randomized 1,005 individuals with stage T3 prostate cancer and/or positive surgical margins to receive either adjuvant radiotherapy or a wait-and-see approach after prostatectomy.
The magnitude of benefit of postoperative radiotherapy on disease-free survival, compared to a wait-and-see approach, was greatest in patients with positive surgical margins. The researchers calculated that irradiation could prevent 291 events per 1,000 patients with positive margins versus 88 events per 1,000 patients with negative margins.
"Our subset analysis of these patients showed that adjuvant radiotherapy reduces the risk of biochemical recurrence specifically in those with positive surgical margins, whereas those with negative margins (irrespective of other risk factors) in general do not seem to benefit," the authors write.