Stereotactic Ablative Body Radiation Two weekly fractions of:
13 Gy to whole prostate +/- seminal vesicles AND Up to 16 Gy simultaneous boost to dominant MRI nodule
Treatment Delivery and Quality Assurance Treatment will be delivered on treatment units equipped with with volumetric arc therapy and hexapod couches. Only photons with megavoltage energies of 6 MV will be used. Cone-beam CT imaging will be performed using the implanted fiducials to set up each treatment. Imaging after each fraction of radiation will be performed and the shifts in prostate positioning (as measured by displacement of gold seed fiducials) will be measured and recorded. Also, the total treatment time for each fraction of radiotherapy will be recorded.
Patient Assessments / Follow-up Time zero will be the start of radiotherapy. Baseline and follow-up parameters are as listed in Appendix A. Baseline rectal and urinary function will be recorded. Acute toxicities will be assessed at weeks 1, 4, and 13 and late toxicities will be assessed at month 6 and every 6 months until year 5 using the Common Terminology Criteria Adverse Events, version 4.0. Bloodwork (PSA and testosterone), will be performed at months 3, 6 and every 6 months until year 5. QOL using the Expanded Prostate Cancer Index Composite (EPIC) will be obtained at baseline, weeks 1, 4, 13, month 6 and every 6 months until year 5.
