- The post-therapy excision specimen will be processed in a standard fashion. Pathologic features, margin status, and tumor size will be assessed by a light microscopic examination of histological sections. In addition to this routine processing, immunohistochemistry assays for proliferation (Ki67), apoptosis (TUNEL), HER2, TP53, cyclin D1, p27, BCL2, ER, and PR will be performed. For correlative biological studies pathologists will select approximately .5 cubic mm representative sections of the neoplastic tissues and normal adjacent breast tissue, which will be snap frozen for gene expression analysis using microarrays.