Use of a Biodegradable Balloon for the Treatment of Prostate Cancer by Intensity Modulated Radiotherapy (BioPro-RCMI)

Patients eligible for the trial and having signed their consent to participate will undergo a scan to verify the possibility of implantation of the balloon. Before and after implantation of the balloon, a dosimetric scan will be performed. Radiotherapy will be administered according to the habits of each centre : Intensity modulated radiotherapy : 2 Gy / session, 5 weekly sessions, total dose of 74-80 Gy (+/- associated with an hormone therapy). Patients will have a clinical examination : * prior to the start of treatment * once a week during the radiotherapy * at the end of the radiotherapy * and at the end of the study. They will also complete quality of life questionnaires : * prior to the start of treatment * at mid-treatment * at the end of the radiotherapy * and at 3, 6, 12 and 24 months after the end of the radiotherapy. Finally, patients will undergo a laboratory examination : * prior to the start of treatment * 3 months after the end of the radiotherapy * and then every 6 months.