Figure 3

HCA of prominent significant wavenumbers. Dendrogram showing general and sub-clusters of lung cancer (C) and normal (N) sputum spectra produced by HCA using significant panel of wavenumbers. Supplementary information for samples are provided at the bottom of the plot: y = smoker, n = never-smoker, x = ex smoker, Previous diagnoses of other cancers are also labelled: * = breast, ‡ = larynx and bladder, † = colorectal. Normal cases who had stated that they had a cough prior to providing sputum are labelled with ■.