Raman Spectroscopic Characterization of Human Breast Tissues: Implications for Breast Cancer Diagnosis

Development and application of laser-based diagnostic and therapeutic procedures have been hindered by the current technical inadequacies in tissue diagnosis and characterization. It is now possible to apply the techniques of Raman spectroscopy to achieve rapid, noninvasive, and nondestructive differentiation of diseased from normal tissues. Normal and diseased breast tissues were examined by Raman spectroscopy. The Raman spectra obtained contain features that are attributable to various amounts of carotenoids and lipids. A small contribution from a heme-type signal was detected in some samples of clinically abnormal yet histopathologically benign breast tissue, while a much stronger heme-type signal was detected in most of the breast cancers. Raman spectra of diseased breast tissue (benign and malignant) also show markedly diminished to absent contributions from lipids and reduced contributions from carotenoids. This laser-based spectroscopic modality is readily adaptable to reflected light microscopy and optical fiber techniques, making it potentially useful as an aid in real-time diagnosis, and may thus find application in the fields of histopathology and interventional radiology.