Magnetic resonance imaging-guided focal laser ablation of prostate cancer.

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 or in-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 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 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 systematic biopsies 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, rectal pathology or abdomino perineal resection);
• Metallic hip implant or any other metallic implant or device that distorts local magnetic 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.

Gender identity

The investigators will be author of submitted manuscripts in case they fulfill criteria for authorship according to regulations of scientific journals. After scientific publication of the results the study protocol, relevant data and findings will be made publically available for other centers to implement (parts) of this research into their standard clinical practice if they wish to do so.