A system and method for Raman spectral analysis for diagnostic purposes to identify the disease state of biological tissue. The sampled tissue can be any human or animal tissue, including but not limited to prostate, breast, cervical tissue, etc. Raman spectroscopy is used to provide Raman bands which are decomposed and their chemical fingerprints identified after mathematical modeling. The method enables identification of chemical compounds in the tissue being diagnosed. Comparison with reference samples permits inferences concerning the presence or absence of disease, the stage of disease, and/or the response of disease to treatment. The method provides sufficient information about the chemical composition of the tissue to differentiate between normal and abnormal states, and may also reveal the locations of abnormalities. The method may also be used to monitor the treatment of a subject and/or the response of disease to drugs or other treatments.
