RAD 1802: Pilot Trial of Five Fraction Stereotactic Body Radiotherapy for Early Stage Breast Cancer Patients Eligible for Post-Operative Accelerated Partial Breast Irradiation (APBI)

RAD 1802: A Pilot Trial of Five Fraction Stereotactic Body Radiotherapy for Early Stage Breast Cancer Patients Eligible for Post-Operative Accelerated Partial Breast Irradiation (APBI)

This study offers 5 fractions of radiation treatment through partial breast irradiation in patients with early stage breast cancer after having a lumpectomy.

This study offers 5 fractions stereotactic body radiotherapy for early stage breast cancer after patient undergoes a lumpectomy. The study aims to determine the safety and feasibility of delivering only 5 doses of radiation treatment rather than the longer schedule of treatments that is currently considered standard of care for breast cancer patients. Patients will be followed for 36 months (2 years) with follow-up appointments at 6, 12, 18, 24, and 36 months.

Inclusion Criteria:

• Pathologically proven invasive mammary carcinoma, Invasive ductal carcinoma (IDC) or ductal carcinoma in situ (DCIS) of the breast. Medullary, papillary, mucinous (colloid) and tubular histologies are allowed.
• Age>50.
• Maximum pathologic tumor size <2.0cm if invasive carcinoma or < 2.5cm if pure DCIS.
• Estrogen receptor (ER) positive (>10%).
• Must be eligible for breast conservation therapy and receive a lumpectomy with pathologic margins of at least 2mm.
• Must be clinically node negative by physical examination. Sentinel node dissection is not required, but if undertaken, the patient must be pathologically node negative.
• Zubrod Performance Status 0-2.

Exclusion Criteria:

• Multifocal or multicentric cancer.
• Reception of neoadjuvant chemotherapy.
• Pure invasive lobular histology.
• Inability to clearly delineate lumpectomy cavity on post lumpectomy planning scan.
• Measured maximum PTV of >124cc.
• Lumpectomy cavity within 5mm of body contour.