Patient Derived Breast Cancer Xenografts

This study will use tissue or body fluid acquired during standard procedures that are part of the patient's care for their cancer, such as surgery to remove tumor tissue or needle withdrawal of body fluid containing cancer cells. The tissue or cells will be injected into immune compromised mice and the tissue will be allowed to grow to a tumor 1-1.5 cm size. The tissue will then be extracted and either frozen, embedded in paraffin, or used for engraftment into another generation of mice. The second generation mice will be separated into groups and given various treatments.

Tissue from the participants and from the mouse established tumors, in which the mice have either received treatment or have not received treatment, will be used to evaluate the levels of various genes that assist in regulating cell growth and cell death. The tumor tissue from participants and mice will also be tested for random changes in the genetic material and compared to the participant's blood to determine if any of the changes in the genetic material correlate with better engraftment of the patient tissue in the mice. It is anticipated that 10-30% will have successful engraftment of tumor tissue