Pre-Treatment:
Planning CT and mpMRI imaging for SABR TRUS with biopsy and insertion of Gold Seed Fiducial Markers Biobanking of urine, blood and biopsy tissue (as per REB#079-2006 Odette Cancer Centre (OCC) biobanking protocol)
Stereotactic Ablative Body Radiation (SABR):
13.5Gy x 1 to whole prostate + 1cm seminal vesicles 2 weeks post-planning, treatment will be delivered as per standard treatment protocols on SABR-compatible linear accelerator with a six-degree of freedom couch. Cone-beam CT imaging will be performed using the implanted fiducials to set up each treatment. All dosimetric parameters will be recorded.
Inter-treatment (approx 1 week post-SABR):
Planning mpMRI and TRUS imaging for HDR Biobanking of urine and blood (as per REB#079-2006 OCC biobanking protocol)
HDR brachytherapy:
13.5 Gy x 1 to the prostate, <20 Gy to DIL Approx 2-3 weeks post-SABR, the HDR dose prescription of 13.5 Gy to the whole gland and <20 Gy to MRI visible lesion will be delivered in one fraction, assuming that dose constraints to critical organs can be met. All dosimetric parameters will be recorded Patient Assessments / Follow-up Time zero will be the date of SABR treatment. Baseline rectal, urinary and sexual function will be recorded prior to treatment. Acute toxicities will be assessed at 6, 12 and 24 weeks and late toxicities will be assessed at month 9, 24 and every 6 months until year 5 using the Common Terminology Criteria Adverse Events, V 4.0. Bloodwork (PSA and testosterone) and International Prostate Symptom Score (IPSS) evaluations will be performed at baseline week 6, month 3, 6, 9 and 24, and every 6 months until year 5. QOL using the Expanded Prostate Cancer Index Composite (EPIC), EQ-5D and PORPUS questionnaires will be obtained at baseline, month 3, 6, 9 and 24 and every 6 months until year 5. Post-treatment biobanking will be done at 13 and 52 weeks (as per REB#079-2006 OCC biobanking protocol)