LAUSR

TPS153Background: The development of Stereotactic Body Radiotherapy (SBRT) has provided a further treatment option for early stage prostate cancer. In addition to the benefits of an overall treatment time reduction, profound hypofractionation could result in therapeutic gain given the radiobiology of prostate cancer. Evidence suggests SBRT to be safe and effective; however randomised data is lacking comparing outcomes with standard treatment options. Aim: To assess whether SBRT offers therapeutic benefit in comparison to prostatectomy or standard radiotherapy. Methods: The PACE trial is an international multicentre phase III trial, comprising two parallel randomisation processes. Within PACE A, potential surgical candidates are randomised between radical prostatectomy and SBRT (36.25 Gy in 5 fractions). In PACE B, randomisation is between standard radiotherapy (78Gy in 39 fractions or 62Gy in 20 fractions) and SBRT (36.35Gy in 5 fractions). SBRT can be delivered using Cyberknife or gantry based techniques...