ABlative Radiotherapy (for) Unfavorable Prostate Tumors 2.0

Published clinical evidence confirms that a single dose of 24 Gy provides unprecedented long-term local control in primary and metastatic prostate cancer with safe toxicity profiles, provided that exposure of surrounding healthy tissues is critically assessed with fulfillment of strict constraints and dose distribution is accomplished using image guidance and tracking tools. In the present trial, intermediate unfavorable and selected high-risk organ-confined prostate cancer patients will undergo Single Dose Radiation Therapy (SDRT) With Focal Boost to the MRI-defined Macroscopic Tumor Volume by means of image-guided volumetric intensity-modulated arc radiotherapy (IGRT-VMAT) and state-of-the-art treatment-planning and quality assurance procedures. Androgen Deprivation Therapy (ADT) type and duration has been set as per standard of care, in accordance with current recommendations and guidelines. The results of the study will enable us to find out if the new, shorter treatment (1 doses of radiotherapy), has a similar level of side effects as the 5 dose treatment and is suitable for further study.

Sex

Male

Minimum age

18 Years

Maximum age

90 Years

Inclusion Criteria:

* Histologically proven prostate adenocarcinoma;
* Intermediate and High risk disease, as per the NCCN definition;
* a PI-RADS 3-5 dominant intraprostatic lesion on multiparametric MRI (mpMRI);
* N0M0 at staging with standard techniques (Bone Scan and Abdominal CT) or (preferably) PSMA PET-CT;
* World Health Organization performance status 0-1;
* Life expectancy of \> 5 years, in the opinion of the investigator;
* IPSS score must be ≤ 15 (alpha blockers allowed);
* Prostate gland volume ≤100 g as estimated by computed tomography (CT), ultrasound, or MRI.

Exclusion Criteria:

* ≥T3b disease according to the 8th AJCC classification;
* PSA\>20 ng/ml;
* Previous local treatment of the prostate with surgery (radical prostatectomy or cryotherapy) or transurethral resection;
* Previous radiotherapy to the pelvis;
* Presence of a periurethral dominant lesion;
* Previous invasive malignancy unless disease free for a minimum of 5 years;
* Active Crohn's Disease or Ulcerative Colitis;
* Presence of hip prostheses.

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