Transcutaneous in vivo Raman spectroscopy of breast tumors and pretumors

Abstract

Breast cancer is the most common cancer amongst women worldwide. Early detection of this cancer results in better prognosis. Owing to the disadvantages of currently available screening tools for early detection of this cancer, rapid and sensitive alternatives such as optical spectroscopic techniques are being extensively explored. Detection of premalignant lesions using these techniques has been reported. However, premalignant lesions are risk indicators and may not be true predictors of tumor development. Therefore, the current study aims at correlation between spectral changes and tumor appearance. In this context, transcutaneous in vivo spectra were acquired from same carcinogen‐induced rats immediately before carcinogen treatment, 3, 8–10, and 12–14 weeks after carcinogen treatment and from frank tumors. These were analyzed using multivariate statistical tools principal component analysis and principal component linear discriminant analysis. Further, a complex test data set consisting of spectra from rats of varying ages, tumor appearance times, and tumor induction protocols was used to test the feasibility of correctly identifying controls and pretumors using Raman spectroscopy. Results suggest feasibility of distinguishing pretumor spectra from controls. Taking into consideration the heterogeneity of afflicted breast, rat‐wise analysis was performed wherein a rat was declared ‘will develop tumor’, even if one spectrum was found abnormal. Using this criterion, in vivo Raman spectroscopy could predict tumor appearance with 82% sensitivity and 95% specificity. Prospectively, combined with emerging technologies like deep Raman spectroscopy and fiber‐probe‐based whole sample imaging, Raman spectroscopy may prove as an invaluable adjunct to currently available breast cancer screening tools. Copyright © 2015 John Wiley & Sons, Ltd.

Based on Serum Raman and Fluorescence Spectra to Diagnose Liver Cancer

“…Raman scattering detects the vibrational frequency of molecular chemical bonds, and this intrinsic property makes Raman scattering have ultrahigh chemical resolution ability. It is also important in this way, that is, it does not require the addition of external labels to distinguish different components and is a non-labeling technique [10][11][12] . In the medical eld, the occurrence of diseases often starts from subtle variations inside the molecules, which are di cult to detect by routine clinical means, such as changes in the structure of proteins, fats, sugars and nucleic acids [13][14][15] .…”

In vivo Raman spectroscopy of breast tumors prephotodynamic and postphotodynamic therapy

“…Also evident were nucleic acid bands (752, 788, 828, 1,082, and 1,340 cm −1 ) and 1,526 cm −1 carotenoid band . The dominance of proteins in tumor spectra is well documented in literature . As opposed to normal breast, which has lipid dominance, destruction of breast architecture and malignancy associated biochemical changes result in increased protein in tumors .…”

Recent advances in linear and non‐linear Raman spectroscopy. Part X

“…Bhattacharjee and co‐workers reported on the transcutaneous in vivo Raman spectroscopy of breast tumors and pretumors. They conclude that, combined with emerging technologies like deep Raman spectroscopy and fiber‐probe‐based whole sample imaging, Raman spectroscopy may prove as an invaluable adjunct to currently available breast cancer screening tools . Buckley et al .…”

“…They conclude that, combined with emerging technologies like deep Raman spectroscopy and fiber-probe-based whole sample imaging, Raman spectroscopy may prove as an invaluable adjunct to currently available breast cancer screening tools. [43] Buckley et al described progress towards the in vivo prediction of fragility fractures in bone with Raman spectroscopy. To reach their goals, they are developing Spatially Offset Raman Spectroscopy (SORS) as a tool for retrieving chemical information from bone non-invasively in vivo.…”