Alpha Radiation Emitters Device (DaRT) for the Treatment of Locally Recurrent Prostate Cancer

Inclusion Criteria: * Histologically and/or cytologically proven prostate adenocarcinoma * Biochemical recurrence by the Phoenix definition (PSA nadir + 2 ng/mL) and confirmed by a pre-treatment biopsy. * Patients eligible for focal salvage brachytherapy * Clinical stage T1-T2 on relapse; unilateral extracapsular extension (T3a) on MRI permitted except posteriorly relative to the rectum * Pre-salvage PSA level (rPSA) \< 10 ng/ml * Target lesion is technically amenable for Alpha DaRT sources implantation. * Targetable lesion by either PSMA PET-CT according to PERCIST v1.0 OR by multiparametric MRI according RECIST v1.1 (Patients who were classified as stage II according to MRI) * Lesion size ≤ 5 cm in the longest diameter * ECOG Performance Status Scale 0 - 2 * Life expectancy is more than 6 months * WBC ≥ 3500/µl, granulocyte ≥ 1500/µl * Platelet count ≥60,000/µl * Creatinine ≤1.9 mg/dL * AST and ALT ≤ 2.5 X upper limit of normal (ULN) * INR \< 1.4 for patients not on Warfarin * Age ≥ 40 years old * Subjects are willing and able to sign an informed consent form * Patients must agree to use adequate contraception (vasectomy or barrier method of birth control) for 3 months after DaRT insertion Exclusion Criteria: * Concomitant immunotherapy within the past 4 weeks. * Patients with lymph node or metastatic disease * Known hypersensitivity to any of the components of the treatment. * Patients undergoing systemic immunosuppressive therapy excepting intermittent, brief use of sy…