Follow-up of bronchial precancerous lesions and carcinoma in situ using fluorescence endoscopy

Little is known about the natural history of precancerous bronchial lesions . Histological changes occurring in 416 bronchial intraepithelial lesions ( 104 high-risk subjects) were assessed over a 2-yr period, using repeated fo llow-up autofluorescence endoscopies. During the study, 6 of 36 normal epit heliums became dysplastic; 47 of 152 metaplasia evolved to low-grade dyspla sia, two progressed to carcinoma In situ, and one to invasive cancer; 6 of 169 low-grade epithelial lesions progressed to a persistent severe dysplasi a; 10 of 27 severe dysplastic lesions and 28 of 32 carcinoma in situ persis ted or progressed, respectively (p = 0.0005, severe dysplasia versus carcin oma in situ 24 mo, outcome). Carcinoma in situ appeared more frequent in pa tients with a. prior history or concomitant cancer (p = 0.003). Persistence of smoking during the study did not influence high-grade lesion outcome. P rogression of low-grade epithelial lesions during the study occurred only i n patients with at least a high-grade lesion in another site at baseline (9 of 147 lesions, 6.1%). Our study suggests that low-grade epithelial lesion s could be safely followed-up at 2 yr in patients without high-grade lesion s at baseline, whereas severe dysplasia, should be treated if they persist at 3 mo. Immediate treatment of carcinoma in situ appears warranted.