Inclusion Criteria:  Histological confirmation of prostate acinar adenocarcinoma with a minimum of 10 biopsy cores taken Prostate protocol MRI for local staging  Patients belonging to intermediate unfavorable group according to the D'Amico/NCCN risk group classification:  -Grade group 3 or/and -2-3 risk factors for intermediate category (PSA 10-20 ng/ml/ Grade group 2-3/ cT2b cT2c) or/and -biopsy cores positive ≥50%  Patients belonging to a subclass of high risk group according to the D'Amico/NCCN risk group classification:  -ISUP group 4 (GS 4+4, 3+5, 5+3) or -cT3a stage or PSA>20 Eastern Coooperative Oncology Group (ECOG) PS 0-2 Ability of the patient to understand and sign a written informed consent document Ability and willingness to comply with patients reported outcome questionnaires schedule during the study time IPSS 0-15 Prostate Volume less than 100cc PSA must be dosed maximum 60 days before randomization No pathologic lymph nodes and distant metastasis on PET (fluorocholine) scan or CT scan+bone scan. Contraceptive measures for patients with partners with reproductive potential must be explained  Exclusion Criteria:  History of Malignant tumors in the previous 2 years excluding non melanoma cancers of the skin. If a patient presents an anamnesis of malignancy (excluding non melanoma skin cancers) it must be free from disease since 24 months at the time of enrollement. Previous prostate surgery other than TURP (at least 6 weeks prior to start of SBRT). Previous pelvic RT Prior androgen deprivation therapy (excluding 5alpha reductase inhibitors) Any prior active treatment for prostate cancer; patients on previous active surveillance are eligible if inclusion criteria are met Active severe inflammatory bowel disease Bilateral hip prothesis or any implant that could seriously interfere with dosimetric calculations Age >80 years. cT4a, cT3b or pelvic lymph node involvement Controindication or hypersensitivity to the use of Triptoreline 5alpha reductase inhibitors not discontinued 4 weeks prior to randomization History of bone fractures and fall Risk factors for abnormal heart rhythms or QT prolongation. Use of concomitant medications that prolong the QT/QTc interval