A Study of Diffusing Alpha Radiation Therapy for Patients With Breast Carcinoma in Frail or Elderly Patients.

Inclusion Criteria:

• Histologically confirmed invasive breast tumor with no involvement of skin within 12months.

• Tumor size ≤ 4 centimeters in the longest diameter.

• Tumor is not deemed as resectable with radical surgery or the patient does not wishto go through surgery

• De-novo or recurrent lesions.

• Single lesion per quadrant per subject.

• Targeted lesion must be technically amenable for complete coverage (includingmargins) by the DaRT seeds.

• Interstitial implant indication validated by multidisciplinary team.

• ECOG Performance Status ≤3.

• Life expectancy ≥12 months.

• Women Age ≥65 or younger if unfit for standard of care.

• Willing and have the ability to provide signed Informed Consent.

• Blood tests values:

• Leucocytes ≥3000mm3,

• Absolute neutrophil count ≥1500mm3,

• Platelets ≥100,000 mm3,

• Total bilirubin ≤ 1.5xULN,

• AST, SGOT, SGPT ≤2.5xULN, If Alkaline Phosphatase ≤ 4xULN, then transaminasesare normal.

• Creatinine ≤ 2.0xULN.

• INR or Prothrombin time ≤1.5xULN

Exclusion Criteria:

• T4 category with skin involvement.

• Ductal carcinoma in situ.

• Inflammatory breast carcinoma.

• Longest tumor diameter >4 cm.

• Patients with prior radiation to the same area within the past 6 months.

• Has a known additional malignancy that is progressing or requires active treatment.

• Patients undergoing immunosuppressive and/or systemic corticosteroid treatmentexcept for steroid inhalations for treatment of asthma or lung disease

• Subjects not willing to sign an informed consent.