MRI-guided Focal Laser Ablation

Inclusion criteria:

• MRI visible index lesion (on T2-weighted MR imaging or diffusion weighted imaging);
• Maximum MRI visible lesion size is ≤ 15 mm large axis;
• Life expectancy at inclusion of more 10 years;
• Diagnosis of prostate cancer confirmed by targeted biopsy using TRUS-MRI fusion orin-bore MRI guided biopsies;
• 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 targetedbiopsies, serum prostate specific antigen < 15 ng/ml);
• Patient accepting to be included in an active surveillance protocol at the end of thestudy, 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 chronicprostatitis;
• History of tumor in the preceding 5 years (excluded: non-metastatic basal cell skincancer);
• Severe urinary symptoms associated with benign hyperplasia of the prostate, anddefined by an IPSS score > 18;
• Tumor with MRI signs of extra-capsular extension or invasion of the seminal vesicles;
• Maximum cancer core length >3 mm and/or maximum Gleason score of 3+4 on systematicbiopsies outside the visible tumor area on mpMRI;
• 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, rectalpathology or abdomino perineal resection);
• Metallic hip implant or any other metallic implant or device that distorts localmagnetic field and compromises the quality of MR imaging;
• Patients with evidence for nodal or metastatic disease;
• Patients with an estimated Glomerular Filtration Ratio (eGFR) < 40 mL/min/1.73 m2.