MRI-guided Focal Laser Ablation Prostate Cancer

Inclusion Criteria: * MRI visible index lesion (on T2-weighted MR imaging or diffusion weighted imaging); * maximum MRI visible lesion size is ≤ 20 mm large axis; * age 45 to 76 years old; * life expectancy at inclusion of more 10 years; * diagnosis of prostate cancer confirmed by targeted biopsy; * criteria of low and intermediate risk of progression and eligibility for focal therapy; * clinical stage of maximum T2c * maximum biopsy Gleason score of 4 + 3 on targeted biopsies * serum prostate specific antigen \< 15 ng/ml * patient accepting to be included in an active surveillance protocol at the end of the study, in accordance with the recommendations of good practice. Exclusion Criteria: * History of prostate surgery; * history of radiation therapy or pelvic trauma; history of proved acute or chronic prostatitis; * history of tumor in the preceding 5 years (excluded: non-metastatic basal cell skin cancer); * severe urinary symptoms associated with benign hyperplasia of the prostate, and defined by an IPSS score \> 18; * tumor with extra-capsular extension or invasion of the seminal vesicles; * patients with \>2 lesions; * impossibility to obtain a valid informed consent; * patients unable to undergo MR imaging, including those with contra-indications; * contra-indications to MR guided focal laser therapy (colitis ulcerosa, rectal pathology or abdomino perineal resection); * metallic hip implant or any other metallic implant or device that distorts local magnetic …