Neoadjuvant Interstitial Brachytherapy Using Diffusing Alpha Emitters Radiation Therapy in Men With Prostate Cancer

The study is planned as a prospective, open-label, one arm, single center trial, designed to assess the feasibility and safety of intratumoral DaRT seeds implantation for the treatment of local prostate cancer prior to surgery.

This approach combines the advantages of local intratumoral irradiation of the tumor, as used in conventional brachytherapy, with the power of the alpha radiation emitting atoms, that will be introduced in quantities considerably lower than radiation therapy already used in patients.

Prostate lesions with histopathological confirmation of adenocarcinoma will be treated using DaRT seeds in a neo-adjuvant setting.

Feasibility will be assessed by the successful delivery of DaRT seeds into the intratumoral environment. In addition, objective response rate will be assessed both by imaging and pathology.

Inclusion criteria

• Pathologically confirmed, previously untreated, resectable prostate adenocarcinoma
• Ability to provide tissue sample from the target or its vicinity, either from an archive or undergo another biopsy to provide a fresh sample
• Medically fit for surgery
• Targetable lesion must be technically amenable for complete coverage (including 3-5mm margins) by the DaRT seeds
• Targetable lesion by either PSMA PET-CT according to PERCIST v1.0 OR by multiparametric MRI according RECIST v1.1
• Patients must be willing to undergo imaging before and after treatment with DaRT (prior to surgery)
• Lesion size ≤ 3 cm in the longest diameter
• Age ≥ 18 years old
• ECOG Performance Status Scale ≤ 1
• Subjects' life expectancy is more than 6 months
• WBC ≥ 3500/μl, granulocyte ≥ 1500/μl
• Platelet count ≥ 100,000/μl
• Calculated or measured creatinine clearance ≥ 60 cc/min
• AST and ALT ≤ 2.5 X ULN
• INR <1.4 for patients not on Warfarin
• Subjects are willing and able to sign an informed consent form

Exclusion criteria

• Documented evidence of distant metastases
• Prior TURP or prostate surgery
• Prior pelvic radiation
• Any prior pelvic malignancy or other malignancy in the last 5 years, except for cured non-melanoma skin cancer
• Inability to undergo MRI (i.e. permanent implanted device incompatible with MRI)
• Known hypersensitivity to any of the components of the treatment.
• Clinically significant cardiovascular disease, e.g. cardiac failure of New York Heart Association classes III-IV, uncontrolled coronary artery disease, cardiomyopathy, uncontrolled arrhythmia, uncontrolled hypertension, or history of myocardial infarction in the last 12 months.
• Any medical or psychiatric illness which in the opinion of the investigator would compromise the patient's ability to tolerate this treatment or interfere with the study endpoints.
• Patients must agree to use adequate contraception (vasectomy or barrier method of birth control) prior to study entry, for the duration of study participation and for 3 months after DaRT implant procedure
• Volunteers participating in another interventional study in the past 30 days which might conflict with the endpoints of this study or the evaluation of response or toxicity of DaRT.
• High probability of protocol non-compliance (in opinion of investigator)
• Subjects not willing to sign an informed consent