To evaluate the rate of patients without cancer detected by biopsies performed six months after hemi-ablation with high intensity focused ultrasound (HIFU) (Ablatherm ®).

Evaluate the impact of the HIFU treatment on continence, sexuality and quality of life at one year. Evaluate the cost of hemi-ablation HIFU treatment.

A prospective single -centre phase II, single arm, cohort study (therapeutic confirmatory) offering focal therapy using HIFU (Ablatherm ®) to 25 men with histologically proven localised low to intermediate risk prostate cancer (PSA ≤10ng/ml, Gleason score ≤ 7 ,T1c or T2b ). Precise mapping and characterisation of the disease will be established using multi-parametric (mp)-MRI and prostate biopsies. Only the lobe with disease will be treated.

Inclusion Criteria:

• Age≥ 50 years
• Clinical stage T1c (normal digital rectal examination) or T2a (one palpable nodule on digital rectal examination)
• PSA ≤10 ng / mL
• Presence of cancer on biopsies (12 sampling biopsies plus 2-4 targeted biopsies on one side and limited to one or two contiguous areas of prostate: basic and middle or middle and apex).
• Gleason score ≤ 7 (3+4)
• Flowmetry > 12 mL / sec for a voided volume of 125 mL
• PVR <100 mL
• Patient with normal anal and rectal anatomy.
• Patient with a condition corresponding to a classification of ASA 1 or 2.
• Patient signing ICF and agreed for following monitoring

Exclusion Criteria:

• Patient with an ASA score 3.
• Patient in clinical stage T1a, T1b, T2b, T2c or T3.
• Patient with a tumor visible on MRI: Located at a distance less than 5 mm from the midline. Located less than 6 mm from the apex real
• Metastatic lymph node or metastasis discovered by MRI and bone scan.
• Patient previously treated for his prostate cancer by hormone therapy.
• Patient with a distance between the rectal mucosa and prostate capsule over 8 mm thick
• History of inflammatory bowel disease
• Rectal fistula.
• History of pelvic radiotherapy.
• History of bladder cancer.
• History of bladder neck sclerosis or urethral stenosis.
• Patient with an implant located less than 1 cm from the treatment zone (stent, catheter).
• Urogenital infection.
• Latex allergy
• Contraindication to MRI (pacemaker,metal prosthesis ...)
• Patient participated in another clinical study within 30 days.
• Illiterate patients
• Legally incapable patients