Genetically-Guided Radiotherapy for the Treatment of Triple Negative Breast Cancer in Patients Undergoing Breast Conservation Surgery

Inclusion Criteria

• Patients should have undergone breast conservation therapy with a lumpectomy and axillary evaluation to consist of a sentinel node biopsy or axillary dissection
• Confirmation of TN breast cancer by tissue biopsy
• Adequate tissue to calculate RSI
• For patients undergoing neoadjuvant chemotherapy, residual tumor burden should be noted. For patients with a pathologic complete response in which RSI cannot be calculated they will remain eligible for assessment of tertiary objectives
• To fulfill the requirement of HER2- disease, a breast cancer must not demonstrate, at initial diagnosis or upon subsequent biopsy, overexpression of HER2 by either immunohistochemistry (IHC) or in-situ hybridization as defined by the American Society of Clinical Oncology (ASCO) / College of American Pathologists (CAP) Guidelines
• To fulfill the requirement of hormone receptor (HR)- disease, a breast cancer must express (< 10%), by immunohistochemistry (IHC), the hormone receptors (estrogen receptor [ER] and progesterone receptor [PR]) as defined in the American Society of Clinical Oncology (ASCO) / College of American Pathologists (CAP) Guidelines
• Life expectancy >16 weeks
• Karnofsky Performance Status (KPS) >= 70
• Age >= 18 years
• Patients with surgery within 14 days should have recovered from all effects of the surgery and be cleared by their surgeon
• There is no limit on prior systemic therapies
• A minimum of 2 weeks is required from the completion of systemic chemotherapy
• Radiation therapy should begin within 16 weeks of the later of these two dates: the date of final breast conserving surgery or the date of the last infusion of cytotoxic chemotherapy
• Women of childbearing potential and sexually active males must commit to the use of effective contraception while on study
• Ability to sign an informed consent form, which can be signed by a family member or health care proxy. Informed consent must be given before study enrollment

Exclusion Criteria

• Women who are pregnant or breastfeeding
• Patients not undergoing breast conservation therapy
• Metastatic breast cancer
• Positive lumpectomy margins on final pathology
• Patients with a history of non breast cancer malignancy should have no evidence of disease >= 2 years
• Prior history of breast cancer in the ipsilateral breast (invasive disease or ductal carcinoma in situ [DCIS])
• History of prior or concurrent contralateral invasive breast cancer