Early Salvage Therapy for Patients With Advanced Features for Biochemical Relapse After Radical Prostatectomy for Localized Prostate Carcinoma In Correlation With Supposed Molecular-genetic Parameters of Higher Aggressiveness

Inclusion Criteria: * \> 18 years of age * Pathologically confirmed invasive prostate carcinoma with minimal 1 risk factor (RF) after radical prostatectomy (RP) * Patient refuses the adjuvant therapy after normalization of urinary function within 6 month after RP * Signed informed consent to participate in the study and (where necessary) consent to participate in the translational part of the research (not a requirement) * ECOG 0 - 1 * pT2 and minimal 1 risk factor (RF): * R1 (PSM), and/or * Gleason score (4+3=7) 8-10 and/or ISUP grade group 3-5 * pT3a /pT3b with or without one RF * No evidence of suspicious pelvic lymph nodes by initial diagnostic: cN0 and/or pN0 * No evidence of suspicious distant metastases by initial diagnostic: M0 * Patient with decline of PSA level to undetectable PSA levels (\< 0,1 ng/ml) or around 0,2ng/ml and with another decreasing trends so that the PSA level decline within 12-24 weeks after RP to undetectable levels (\< 0,1 ng/ml) and with renewed increase of PSA \>0,2 ng/ml (BCR= biochemical relapse) without any clinical relapse on PSMA PET/CT * No hormonal therapy prior and /or after the radical prostatectomy * Patient suitable and fit for subsequent radiotherapy with high likelihood of good compliance to the follow-up Exclusion Criteria: * Life expectancy (based on Charlson comorbidity index) \< 10 years * Patient not fit for the therapy * History of other cancer (other than a radically removed non-melanoma skin carcinoma) * Previous pelvic irradiation * Active immunosuppressive medication * History of hormone therapy prior to randomization * cN1 and/or pN1 and M1 * PSA-persistence after RP (PSA 12-weeks after RP \> 0.1 ng/ml or no decreasing trend described in Inclusion criteria)