Design: In this feasibility study, we plan to collect fresh frozen and fixed tissues (tumor and adjacent normal) from approximately 100 breast cancer cases who have given consent to participate in our breast tissue collection pilot study. DNA and RNA will be extracted from frozen tumors and assessed for quality and yield. We will then conduct expression profiling analysis in a subset of cases (N approximately 10) to determine the quality of RNA in molecular profiling analysis. We will also determine whether there are enough epithelial benign and tumor tissues for the construction of tissue microarrays (TMAs). The results from this feasibility study will inform our decision on whether or not to pursue a large scale study.