ABlative Radiotherapy (for) Unfavorable Prostate Tumors

Patients enrolled in this observational prospective trial will be offered image-guided, volumetric modulated radiotherapy (IGRT-VMAT) in a single session (SDRT) of 21 Gy to the whole gland with a simultaneous boost of 24 Gy to the macroscopic PI-RADS driven (4-5) tumour(s). ADT will be prescribed concomitantly, as per standard of care. A real time non-ionizing prostate monitoring will be used to account for intra-fractional errors. If the dose constraints to the normal tissues are at risk, these will be prioritised over the aimed boost dose. The primary endpoint of the trial is the treatment related toxicity measured by the CTCAE v5.0. Secondary endpoints are quality of life in different domains (sexual, rectal , urinary) and biochemical outcome. Patients will be followed at one month, then every 3 months for the first 12 months and every 6 months thereafter. Quality of Life will be prospectively evaluated through validated tools (ECOG, EPIC, IIEF-5, IPSS, ICIQ-SF) at various timepoints. Percentage or total mean score will be reported according the questionnaires, whether they grade values in a scale or use descriptive statistics. Kaplan-Meier curve analysis of biochemical relapse free survival (b-RFS) at 2 and 5-year bRFS for all patients will be estimated.