Merglen et al1 suggested that radical prostatectomy provides the best chance of long-term survival. The authors performed a population-based cohort study including 844 patients with localized prostate cancer. Comparing different treatment methods outside of randomized trials is always affected by selection bias. It is well known that patients receiving radiotherapy are older and have more advanced tumor stages and higher comorbidity. The analysis of prostate-specific survival was elegantly adjusted for several prognostic factors.
Kälkner KM. Radiotherapy Dose in the Treatment of Localized Prostate Cancer. Arch Intern Med. 2008;168(12):1352-1353. doi:10.1001/archinte.168.12.1352-b