Breast cancers are the leading cancers among females. Diagnosis by fine needle aspiration cytology (FNAC) is the gold standard. The widely practiced screening method, mammography, suffers from high false positive results and repeated exposure to harmful ionizing radiation. As with all other cancers survival rates are shown to heavily depend on stage of the cancers (Stage 0, 95%; Stage IV, 75%). Hence development of more reliable screening and diagnosis methodology is of considerable interest in breast cancer management. Raman spectra of normal, benign, and malignant breast tissue show significant differences. Spectral differences between normal and diseased breast tissues are more pronounced than between the two pathological conditions, malignant and benign tissues. Based on spectral profiles, the presence of lipids (1078, 1267, 1301, 1440, 1654, 1746 cm(-1)) is indicated in normal tissue and proteins (stronger amide I, red shifted DeltaCH2, broad and strong amide III, 1002, 1033, 1530, 1556 cm(-1)) are found in benign and malignant tissues. The major differences between benign and malignant tissue spectra are malignant tissues seem to have an excess of lipids (1082, 1301, 1440 cm(-1)) and presence of excess proteins (amide I, amide III, red shifted DeltaCH2, 1033, 1002 cm(-1)) is indicated in benign spectra. The multivariate statistical tool, principal components analysis (PCA) is employed for developing discrimination methods. A score of factor 1 provided a reasonable classification of all three tissue types. The analysis is further fine-tuned by employing Mahalanobis distance and spectral residuals as discriminating parameters. This approach is tested both retrospectively and prospectively. The limit test, which provides the most unambiguous discrimination, is also considered and this approach clearly discriminated all three tissue types. These results further support the efficacy of Raman spectroscopic methods in discriminating normal and diseased breast tissues.

The aim of this study was to understand and correlate spectral features and biochemical changes in normal, fibroadenoma and infiltrating ductal carcinoma of breast tissues using Raman spectra that were part of the spectroscopic models developed and evaluated by us earlier. Spectra were subjected to curve fitting and intensities plots of resultant curve resolved bands were computed. This study has revealed that fat (1301 and 1440 cm−1), collagen (1246, 1271, and 1671 cm−1) and DNA (1340 and 1480 cm−1) bands have strong presence in normal, benign and malignant breast tissues, respectively. Intensity plots of various combinations of curved resolved bands were also explored to classify tissue types. Combinations of fat (1301 cm−1) and collagen (1246, 1271, and 1671 cm−1)/amide I; DNA (1340 cm−1) and fat (1301 cm−1); collagen (1271 cm−1) and DNA (1480 cm−1) are found to be good discriminating parameters. These results are in tune with findings of earlier studies carried out on western population as well as our molecular biological understanding of normal tissues and neoplastic processes. Thus the finding of this study further demonstrates the efficacy Raman spectroscopic approaches in diagnostic applications as well as in understanding molecular phenomenon in breast cancers. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 539–546, 2009.This article was originally published online as an accepted preprint. The “Published Online”date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com

This study further supports the efficacy of Raman spectroscopy, in combination with a limit test, for discrimination of normal and malignant colon tissues. The multiparametric limit test approach is user-friendly, and a clinician or minimally trained individual could directly compare the unknown spectra against the available standard sets to make the decision instantly, objectively, and unambiguously.

Breast cancer is one of the leading female cancers. The major drawback of the gold standard of screening, mammography, is the high rate of false reports, aside from the risk from repeated exposure to harmful ionizing radiations. Histopathology, the gold standard of diagnosis, is time consuming and often prone to subjective interpretations. Molecular level diagnosis 'omics' is becoming increasingly popular; among these is metabolomics, diagnosis based on 'metabolic fingerprinting'. In the present article we review a Raman spectroscopic approach to metabolic fingerprinting in breast cancer detection. This review opens with a brief background on anatomical and etiological aspects of breast cancers. We present an overview of conventional detection approaches in breast cancer screening and diagnosis methods, followed by a concise note on the basics of optical spectroscopy and its applications in the screening/diagnosis of breast malignancy. We present the recent developments in Raman spectroscopic diagnosis of breast cancers and also share our experience in Raman spectroscopic classification of normal, benign and malignant breast tissues. Perspectives and current status of Raman spectroscopic screening/diagnosis of breast cancers are also discussed.

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