Correlation of Molecular Markers With Response to Therapy and Breast Cancer Behavior

Inclusion Criteria: High suspicion of or known breast cancer (early or metastatic) Lesion accessible for safe biopsy (as deemed by the treating physician). Age ≥ 18 years. ECOG performance status 0 - 2. Ability to understand and willingness to sign an informed consent document. If receiving therapeutic anticoagulation; it should be discontinued temporarily prior to biopsy for a length of time to be determined by the study doctor. Adequate marrow function, defined as absolute neutrophil count ≥ 1.5 x 109/L and platelets ≥ 100 x 109/L required only for biopsies of vital organs (lung, liver, etc.) Exclusion Criteria: Concurrent disease or condition that would make the patient inappropriate for study participation or any serious medical or psychiatric disorder that would interfere with the subject's safety. Dementia, altered mental status, or any psychiatric condition that would prohibit the understanding or rendering of informed consent. History of serious or life-threatening allergic reaction to local anesthetics (i.e. lidocaine, xylocaine) Pregnant women are excluded because there may be an increased risk to both mother and fetus in the setting of conscious sedation, which is required for biopsies of certain anatomic sites (e.g. liver, lung). Also, ionizing radiation from CT-guided biopsies may pose a risk to the unborn fetus. Cardiac disease making it unsafe to biopsy in the opinion of the treating physician. If patients receiving bevacizumab or other angiogenesis inhibitors are less than 6 weeks from last dose of the angiogenesis inhibitor, they should not undergo research core biopsies of vital organs (lung, liver, etc.) on this protocol because of the concern for the possibility of increased bleeding risk and delayed healing. Patients receiving bevacizumab or other angiogenesis inhibitors who are undergoing a research biopsy of the breast, peripheral lymph node or a skin punch biopsy must be two weeks from the last dose of the angiogenesis inhibitor.