Combined endoscopic evaluation of central lung cancer spread using autofluorescence and spectroscopy

Objective: To estimate the diagnostic value of autofluorescence bronchoscopy with spectroscopy in determination of lung cancer endobronchial spread. Material and methods: The study included 78 patients with central NSCLC stage II-IV. Combined endoscopic investigation included: bronchoscopy in conventional mode (CB), spectroscopy in conventional mode (CS), bronchoscopy in autofluorescence mode (AFB) and spectroscopy in autofluorescence mode (AFS). Integrated system for autofluorescence and spectroscopy was used. The data obtained were compared with the results of histological study of biopsy samples from the respective sites. Results: The sensitivity and specificity of the combination of AFB and AFS was 97.1% and 88.3%, respectively vs. CB and CS - 66,7% and 86,9%, respectively. Maximal diagnostic value had green-red ratio (GRR) - the ratio of intensity in the green range (500-565 nm) to the red range (620-760 nm). For normal tissue mean GRR was 3,4±0,9, on the borders of tumor growth in 97% of the cases did not exceed 2.0 (mean 1,2±0,4) (p = 0.02), over areas of tumor tissue – in all cases less than 1.0 with an average of 0,7±0,2 (p = 0,001). In 97,1% of cases, the data AFB and AFS is fully consistent with the results of histological studies (p = 0,02). In general, in 30,4% cases AFB and AFS more accurately clarified the extent of tumor in comparison with CB and CS. Conclusions: Combination of AFB and AFS helps to objectively and accurately establish the boundaries of the tumor spread in bronchus/trachea.