Inclusion Criteria

1. Women ages ≥ 18 years without known breast cancer.
2. Women ages ≥ 18 with Stage 0-III breast cancer may donate tissue from the uninvolved breast and may donate blood.
       -If  women have not had definitive surgery for newly diagnosed breast cancer, they may donate samples from both the involved and uninvolved breast.

       -For women with Stage 0-III breast cancer who intend to donate breast tissue: Concurrent hormonal treatment is permitted (tamoxifen, aromatase inhibitors, etc…). Women receiving chemotherapy or biological therapy for their breast cancer cannot have had treatment within 90 days prior to tissue donation.

      -Women who have Stage IV breast cancer are not able to donate breast tissue but may participate in all other aspects of the study

Exclusion Criteria

1. For the purpose of invasive breast biopsies, women may not have breast implants in place.
    -Women who have undergone breast reduction surgery are permitted to donate breast tissue, so long as the surgery is noted on their medical questionnaire

2. Dementia, altered mental status, or any psychiatric condition that would prohibit the understanding or rendering of informed consent.

3. For biopsy of breast tissue only: History of serious or life-threatening allergic reaction to local anesthetics (i.e. lidocaine, xylocaine)

4. Anti-coagulation. For the purpose of invasive breast biopsies, women may not be receiving therapeutic anticoagulants.  For blood draws, anticoagulants will be permitted.

5. Women with known clotting or bleeding disorders

6. Any other condition, which in the opinion of the physician performing the biopsy procedure would make participation in this protocol unreasonably hazardous for the subject.

7. The breast intended for tissue donation cannot have had prior therapeutic radiation.

8. Any radiation to the whole chest wall.