III. To measure changes in cell proliferation (marker of proliferation Ki-67 [Ki67] labeling index) and apoptosis (terminal deoxynucleotidyl transferase deoxyuridine triphosphate [dUTP] nick end labeling [TUNEL]) in breast cancer samples obtained at diagnostic core needle biopsy (of cancer) or research core needle biopsy (of unaffected breast) with tissue samples obtained at mastectomy. Measure protein expression of related targets in the following order of priority: progesterone receptor isoforms (progesterone receptor [PR]A and PRB), and estrogen receptor alpha (ERα) and TUNEL using immunohistochemistry (IHC) at baseline and after treatment.