Diffuse reflectance spectroscopy: diagnostic accuracy of a non-invasive screening technique for early detection of malignant changes in the oral cavity

Abstract

BackgroundStrong proof-of-principle for utilisation of diffuse reflectance spectroscopy, a non-invasive tool for early detection of malignant changes, has emerged recently. The potential of this technique in distinguishing normal tissue from hyperplastic and dysplastic tissues was explored.MethodsDiffuse reflectance (DR) spectra in the 400–700 nm region were obtained from the buccal mucosa of 96 patients and 34 healthy volunteers. The DR spectral data were compared against the gold standard biopsy and histopathology results. A principal-component analysis was performed for dimensional reduction in the normalised spectral data with linear discriminant analysis as the classifying technique. The receiver operator characteristic curve technique was employed for evaluating the performance of the diagnostic test.ResultsDR spectral features for different lesions, such as normal/healthy, hyperplastic, dysplastic and squamous cell carcinoma (SCC), varied significantly according to the intensity of oxygenated haemoglobin absorption. While the classification based on discriminant scores provided an overall sensitivity of 98.5% and specificity of 96.0% for distinguishing SCC from dysplasia, they were 100.0% and 95.0%, respectively, for distinguishing dysplasia from hyperplasia. Similarly, the analysis yielded a sensitivity of 95.0% and specificity of 100.0% for distinguishing hyperplasia from healthy tissue. The areas under the receiver operator characteristic curves were 0.98 (95% CI 0.95 to 1.00) and 0.95 (95% CI 0.90 to 1.00) for distinguishing dysplasia from SCC and hyperplasia from dysplasia, respectively.ConclusionDR spectral data efficiently discriminate healthy tissue from oral malignant lesions. Diagnostic accuracies obtained in this study highlight the potential use of this method for routine clinical practice.

Ex vivo confocal imaging with contrast agents for the detection of oral potentially malignant lesions

“…Techniques such as reflectance spectroscopy 15 , fluorescence spectroscopy 16 and autofluorescence 17 are being used to extract information from oral mucosa on the basis of the interaction of light with endogenous tissue fluorophores. However, in vivo confocal microscopy reveals the actual cellular structures and as such is a form of in vivo histology.…”

Comparative evaluation of the diagnostic performance of autofluorescence and diffuse reflectance in oral cancer detection: a clinical study

“…PCA and LDA were performed over the fluorescence and reflectance spectral data [16,17]. PCA was used to identify the orthogonal components of the spectra with maximum variance within the complete data set.…”

Non-Invasive Techniques for Detection and Diagnosis of Oral Potentially Malignant Disorders

“…A current DRS system typically consists of an imaging device for recording diffuse reflectance images and a fiber-optic probe for relaying light to and from the instrument . Some studies have showed that information about tissue transformation, obtained in vivo with the aid of the oxygenated hemoglobin spectral ratio (R545/R575) algorithm, was able to differentiate normal mucosa, hyperplasia, dysplasia, and OSCC with high sensitivity and specificity (Table 1) (Mallia et al 2008(Mallia et al , 2010Jayanthi et al 2011). Moreover, Stephen et al (2013) suggested that DRS could be very effective as a screening tool for the location of oral PMDs.…”

“…The diffusely reflected emanating light is greatly affected by tissue morphology, such as nuclear size, distribution, epithelial thickness, collagen content, and the amount of oxy-and deoxy-hemoglobin in the exposed tissue, all of which can vary during carcinogenesis of epithelial tissue (Schwarz et al 2008;Jayanthi et al 2011). A current DRS system typically consists of an imaging device for recording diffuse reflectance images and a fiber-optic probe for relaying light to and from the instrument .…”

“…Raman spectroscopy 97.44-100 77-100 (Li et al 2010;Guze et al 2015) Elastic scattering spectroscopy 72-98 68-75 (Jerjes et al 2004;Sharwani et al 2006b;Green et al 2014) Diffuse reflectance spectroscopy 76-100 76-97 (Mallia et al 2010;Jayanthi et al 2011;Stephen et al 2013) Narrow-band imaging 84.62-96 88.2-100 (Piazza et al 2010;Yang et al 2012b;Yang et al 2013;Shibahara et al 2014;Vu and Farah 2014;Yang et al 2014) Optical coherence tomography 73-100 78-98 (Matheny et al 2004;Wilder-Smith et al 2004;WilderSmith et al 2005;Wilder-Smith et al 2009;Olivo et al 2011;Hamdoon et al 2013;Green et al 2014) Confocal laser endomicroscopy 80 100 (Nathan et al 2014) Confocal reflectance microscopy 73 88 (Olivo et al 2011) Salivary biomarker miRNA-184 n/a n/a (Zahran et al 2015) IL-6 n/a n/a (Sharma et al 2011) oral cancer in 132 patients, and concluded that RB staining seemed promising for the detection of epithelial dysplasia in oral leukoplakia, lichen planus, and leukokeratosis (Du et al 2007). Zhang et al (2013) combined fluorescence spectroscopic techniques with RB staining to detect oral PMDs in an animal model in vivo and reported that the method showed excellent sensitivity.…”