Brief Summary: RATIONALE: Collecting and storing samples of breast tissue from patients who have undergone biopsy or surgery to test in the laboratory may help the study of cancer in the future. PURPOSE: This laboratory study is looking at samples of breast tissue from women who have undergone breast biopsy or surgery.

Detailed Description: OBJECTIVES: * To prove that optical spectra collected by inserting an optical fiber probe into breast tissue through a biopsy needle can be of adequate quality to render a spectroscopic diagnosis. OUTLINE: Optical spectra are acquired from ex vivo samples of normal and malignant breast tissue using diffuse reflectance, fluorescence, and Raman spectroscopy. Tissue spectra are measured using a portable clinical spectroscopy device with front- and side-viewing optical fiber probes that are inserted into the breast tissue through a hollow biopsy needle. After the probes are withdrawn through the needle, cutting biopsies are obtained and the tissue is marked at the site of the spectral measurements. The biopsy specimens are then fixed in formalin and submitted for histopathologic studies using standard light microscopy techniques (i.e., H\&E staining and IHC). Additional histochemical, immunohistochemical, and fluorescent in situ stains may be performed to support the diagnosis or to better understand the spectroscopy results. Medical records are reviewed to obtain information from the pathology report on patient demographics, pathological characteristics of the surgical specimen, and clinical indication for the surgical procedure.