Monitoring Plasma Tumor DNA in Early-Stage Breast Cancer

This study is being done to see if it is possible to use blood samples to predict response to treatment in breast cancer patients receiving preoperative (or neoadjuvant) therapy. Research has shown that most breast cancers release tumor-specific DNA into the blood (that is, DNA that is specific to the tumor cells or cancer). This DNA can be detected in blood testing known as plasma tumor-DNA or "ptDNA." This DNA is separate from that found in the blood and tissue samples which serve as the "instruction book" or "genetic code" for the cells that make-up the human body. The changes in ptDNA before and after treatment, as well as after surgery, may also help investigators to understand more about a patient's risk of cancer returning and long-term outcomes.

Inclusion Criteria: * Newly diagnosed, histologically confirmed invasive breast cancer that is triple negative (estrogen receptor \[ER\], progesterone receptor \[PR\], and HER2-neu negative) or HER2-positive (any ER/PR status) * Unresected, untreated breast cancer that is T2, T3, or T4a-c; any N (nodal status); and M0 (not metastatic) * ECOG Performance Status of 0 or 1 * Planning to receive a neoadjuvant chemotherapy regimen containing a taxane ± an anthracycline for at least 4 cycles. Patients with HER2-positive disease must also be planning to receive HER2-targeted therapy. * Diagnostic tumor material must be available for correlative analyses * Patients must have the ability to understand and the willingness to sign a written informed consent document Exclusion Criteria: * No prior treatment for the current breast cancer, though prior use of selective estrogen receptor modulators (SERMs) or aromatase inhibitors (AIs) for the prevention of breast cancer is acceptable. * Women who are pregnant or nursing are excluded. * No history of another primary malignancy in the last 5 years prior to registration. Patients with prior history of in situ cancer or basal or localized squamous cell skin cancer are eligible.