Evaluating the Safety and Efficacy of a Novel Accelerated Partial Breast Irradiation Regimen

Inclusion Criteria

• •Ability to provide informed written consent.
• •Eastern Cooperative Oncology Group (ECOG) performance status of ≤ 3 or a Karnofsky performance score of ≥ 30%.
• •Willingness to return to Sanford Cancer Center for follow-up.
• •Radiation therapy is planned as part of routine care.
• •On histological examination, the tumor must be either ductal carcinoma in-situ (DCIS) or an invasive ductal carcinoma of the breast.
• •Patients must be ≥ 50 years old.
• •Presence of unifocal tumor.
• •Surgical treatment of the breast must have been a lumpectomy. Placement of surgical clips to delineate the lumpectomy bed is highly recommended, though not required.
• •The final margins of the resected specimen must be histologically free of tumor (≥ 2 mm for invasive adenocarcinoma and ≥ 3 mm for DCIS). Re-excision of surgical margins is permitted. Gross disease must be unifocal with a pathologic invasive tumor size tumor size ≤ 2.0 cm or pathologic DCIS size ≤ 2.5 cm.
• •Patients with invasive breast cancer are required to have axillary staging consisting of a sentinel lymph node biopsy. The sentinel lymph node(s) must be negative for regionally metastatic disease, both on routine H\&E evaluation and immunohistochemical staining. Axillary staging is not required for patients with DCIS.
• •Absence of lymphovascular space invasion.
• •The tumor must be positive for either the presence of the estrogen or progesterone receptor, and either 0 or +1 for the HER-2/neu receptor on immunohistochemical staining.
• •The target lumpectomy cavity must be clearly delineated and the target lumpectomy cavity to the whole breast reference volume ratio must be ≤ 30% based on the CT-simulation scan.
• •Life expectancy of 5 years or longer excluding breast cancer diagnosis(co-morbid conditions taken into considerations by the PI)
• •Women of child-bearing potential must have a negative pregnancy test before their CT simulation, and must agree to use an effective method of birth control during their radiation therapy treatment course.