A Trial Evaluating Toxicity of SBRT and LDRB in Localized Prostate Cancer.

The goal of this clinical trial is to compare SBRT (Stereotactic Body RadioTherapy) to LDRB (Low-Dose Rate Brachytherapy with Iodine-125 seed implant) in patients with low and favourable intermediate-risk prostate cancer. The two main questions it aims to answer are : 1. Does SBRT (Stereotactic Body RadioTherapy) for low and intermediate risk prostate cancer patients will result in less genito-urinary (GU) and gastro-intestinal (GI) toxicities than LDRB (Low-Dose Rate Brachytherapy)? 2. Does prostate cancer patients treated by SBRT have a better quality of life than patients treated by LDRB No randomized trial has yet compared LDRB to SBRT head to head.