To assess the early histological outcomes of tissue ablation, adverse events and genitourinary side-effect profile of focal radiofrequency ablation using a coiled bipolar device to treat localized prostate cancer in men with clinically significant prostate cancer.

The study aims to assess the ability of focal therapy using coiled bipolar radiofrequency device to ablate a pre-defined target tissue zone as well as assess side-effects. The medical device has a coiled configuration and creates thus a "Faraday cage" effect, preventing surrounding tissue damage and the bipolar configuration produces complete tissue thermo coagulation within the limits the coil.

Thereof it is proposed to conduct a prospective development study, offering focal therapy coiled bipolar radiofrequency ablation to men with histologically proven localized prostate cancer which is clinically significant.

Localization and characterization of the disease will be established using multi-parametric magnetic resonance imaging (mp-MRI) and transperineal prostate biopsies. Magnetic resonance (MR)-visible, clinically significant disease will be targeted and focally treated with a margin of normal tissue as big as anatomically possible to obtain an adequate margin of normal tissue around the lesion for effective ablation. Secondary lesions meeting criteria for clinical insignificance will be left untreated and undergo surveillance.

Pre-operative and all post operative imaging will be performed using a scanner and a pelvic phased array receiver, with a pelvic coil. A full protocol of T1 and T2 weighted turbo-spin echo images and a dynamic post gadolinium volume acquisition will be used for both pre-operative diagnostic and planning scans and post-operative assessment by use of the medical device.

The initial transperineal biopsy will already have been performed, prior to invitation to participate in the study, and demonstrating eligibility for inclusion.

The process will involve targeted or mapping biopsies which are concordant with the lesion seen on MRI. In both cases, transperineal biopsies will be taken from the prostate using a brachytherapy grid placed over the perineal skin whilst the man is in the lithotomy position.

They will be given as much time as they need to consider whether or not patients wish to participate. The ones who wish to participate after reading the patient information sheet will undergo a screening visit (first visit) to ascertain whether or not they are eligible for the trial. If so, they will proceed to focal radiofrequency ablation using a coiled bipolar device(second visit), and will be seen at further follow-up visits.

Inclusion Criteria:

• Histologically proven prostate cancer
• A visible lesion on multiparametric Magnetic Resonance Imaging (mpMRI), that is accessible to a treatment based on radiofrequency bipolar electrodes
• Transperineal prostate biopsies (template mapping and/or targeted) correlating with clinically significant lesion in the area of the Magnetic Resonance (MR)-visible lesion
• Absence of clinically significant histological disease outside of the planned treatment zone
• Radiological stage T1-T3aN0M0 disease, as determined by local guidelines
• Serum prostate-specific antigen (serum PSA) \