Autofluorescence bronchoscopy in the detection of squamous metaplasia and dysplasia in current and former smokers

Background: New methods are needed to detect precancerous lesions in lung tissue. We conducted a study to determine the utility of LIFE(TM) (laser-induced fluorescence emission) autofluorescence bronchoscopy for the detection of squamous metaplasia and dysplasia in current and former smokers. Methods: In this prospective, single-center study, 53 participants underwent standard white-light bronchoscopy and 39 underwent both white-light and LIFE bronchoscopy. Bronchial biopsy specimens were obtained from all participants at six predetermined sites using white-light bronchoscopy and from all other sites that appeared to be abnormal in participants who underwent LIFE bronchoscopy. Relationships between LIFE imaging and histologic findings were examined for 245 biopsy specimens obtained from those participants who had undergone LIFE bronchoscopy. Results: LIFE imaging revealed abnormalities designated as either class II or class III in 89 (36.3%) and 16 (6.5%) of the 245 sites examined, respectively, and histopathologic examination showed dysplasia and metaplasia in eight (3.3%) and in 52 (21.2%) of the 245 specimens, respectively. Among the 105 biopsy specimens obtained from sites with abnormal LIFE imaging, only 26 (24.8%) exhibited squamous metaplasia and/or dysplasia, similar to the findings for sites with normal LIFE imaging (34 [24.3%] of 140). Comparison of individuals examined by LIFE imaging with those who underwent white-light bronchoscopy alone revealed no increase in the detection of dysplasia or metaplasia with LIFE bronchoscopy. Conclusion: In this population of current and former smokers, abnormalities detected by LIFE bronchoscopy did not improve the detection of squamous metaplasia or dysplasia.