Micro-Raman Spectroscopy for Optical Pathology of Oral Squamous Cell Carcinoma

Abstract

Micro-Raman spectra of formalin-fixed oral squamous normal and carcinoma tissues, stored at room temperature for 2 months, have been recorded. Spectra were recorded both in the epithelial and subepithelial regions of the tissues. No noticeable spectral contamination due to formalin was observed. Very significant differences between spectra of normal epithelial and malignant epithelial samples were found. No such differences in spectra of subepithelial malignant and subepithelial normal samples could be observed. This study shows that spectra from the epithelial region changes drastically because of malignancy-induced biochemical changes in this region. Major differences between normal and malignant spectra seem to arise from the protein composition, conformational/structural changes, and possible increase in protein content in malignant epithelia. The differences between normal epithelial and subepithelial spectra, as expected, arise mainly from the collagen in subepithelial tissue. Principal component analysis of the combined sets of spectra-epithelial and subepithelial, normal and malignant- showed that very good discrimination can be achieved by Raman microspectroscopy. This study thus validates the suitability of formalin-fixed tissues for optical pathology in oral malignancy.

Improved protocols for vibrational spectroscopic analysis of body fluids

“…agnostic applications has been well investigated and demonstrated, notably in dermal applications [3][4][5][6] but also for many other anatomical sites, including cervix [7,8], skin [9][10][11], lung [12,13], brain [14], oesophagus [15,16], colon [17], prostate [18], nasopharynx [19], larynx [20], oral [21], breast [22,23] and liver [24]. The detailed information of the molecular structure and composition of the tissue provided by Raman and Fourier Transform Infrared absorption (FTIR) spectroscopy ultimately promises an analysis of disease origin and progression.…”

Combined Fourier transform infrared and Raman spectroscopic approach for identification of multidrug resistance phenotype in cancer cell lines

“…[5][6][7][8][9][10] Raman and infrared vibrational spectroscopic techniques have also been exploited for investigating eukaryotic and prokaryotic cells. [11][12][13][14][15] As can be seen from the literature, among these two methods, infrared, probably due to its higher sensitivity, has been most widely used.…”

Optical diagnosis of cervical cancer by fluorescence spectroscopy technique

“…Thirdly, in epithelial cancers the abnormal proliferation starts near the basal lamina and advances into the epithelial region, and eventually in the invasive stage penetrates in the connective tissue region. We have shown 31 by Raman spectroscopy that in biopsied tissue samples of oral cancer, the sub-epithelial region showed very similar spectra for normal and malignant samples, and only the epithelial spectra discriminated between the 2 very well. This indicates that unless one is sure which region (epithelial, sub-epithelial or connective tissue) one is looking at in a malignant sample there can be both normal and malignant types of spectra from adjacent sections of the same sample.…”