Cost-utility of Focal HIFU vs Prostatectomy (EMERHIT)

Inclusion Criteria: 50-75 yo male harboring a non-treated localized PC, with a maximum Gleason score of 3+4 , ISUP 2 and less than 50% of positive prostate biopsy (favorable intermediate risk), with or without contralateral microfocus score 3+3 (ISUP 1) of less than 3 mm. Tumor visible on MRI and proven by systematic and targeted biopsies a according to the center's practices, regardless of the route used (transrectal or transpirenal) Patients under active surveillance in whom follow-up Prostate Biopsies reveal ISUP2 with less than 50% of Prostate Biopsies affected Tumor involving maximum 2 biopsy-proven contiguous sextants. Patients with multiple MRI targets may be included if only one target is biopsy-proven. T1c-T2 stage. PSA <20 ng/ml. Prostate volume less than 100 ml. Fully informed patient accepting, after a decent reflexion time, to participate to the study by signing a consent form. Affiliated or beneficiary patient to the social security system. Exclusion Criteria: Metastatic prostate cancer. Gleason score > 3+4 (ISUP>2). More than 50% of positive biopsies. Previous treatment anterior for the same cancer, whatever modality. Contra-indication to pelvic MRI with gadolinium injection. Contra-indication to surgery or general anesthesia. Patient who refuse the one-year follow-up control biopsy after F-HIFU. Presence of implant (stent, catheter) less than 1 cm from the treatment area. Urinary or rectal fistula. Anal or rectal stenosis or any other abnormality that may interfere with the Focal One® endorectal probe introduction. Anatomic abnormality of the rectum or rectal mucosa. Presence of a urinary artificial sphincter, a penile prosthesis or intraprostatic implant, i.e. urethral prosthesis. Bladder neck and/or urethral stenosis or sclerosis. Inflammatory bowel disease (colon or rectum). Ongoing UTI (should be treated before the F-HIFU or the RP). Previous anal or rectal surgery that may interfere with the anal probe introduction. Latex allergy. Rectal wall thickness > 10 mm. Tumor not accessible to a F-HIFU treatment (tumors located in the fibro-muscular anterior zone). Previous not controlled cancer and/or treated since less than 5 years (except basocellular skin cancer). Patient not able to understand the trial objectives or refusing to adhere to the trial instructions. Patients under law-protection. Patient in an ongoing research trial. Patient with a severe health or psychologic problem that could impair the protocol pathway.