File Name : supplementary-figure1.tif

Caption : supplementary figure 1: graphical representation of significant peaks showing the variance in peak intensity expressed as fold change with respect to healthy volunteer (hv) group via difference between the mean spectra approach (dbms). figure 1a represents the ftir spectral data and figure 1b represents the raman spectral data. ‘*’, ‘**’, ‘***’, ‘#’, ‘ns’ indicates p<0.001, p<0.01, p<0.05, p<0.1 and p = non-significant respectively when cs, pc and cp were compared to hv group by one-way anova. abbreviations: cs – cigarette smoker; pc – pre-cancer patients; cp – cancer patients

File Name : supplementary_figure 2.tif

Caption : supplementary figure 2: variance plot of the pca-lda analysis of individual and combined ftir and raman spectroscopic data. figure a and d represent the ftir spectral data variance, b and e represent the raman spectral data variance and c and f represent the combined ftir-raman spectral data for spectra-wise and patient-wise approach respectively.