Fluorescence as a guide to bronchial biopsy.

The presence of fluorescence was assessed in 34 unselected patients undergoing bronchoscopy, 11 of whom suffered from bronchial carcinoma. Bronchoscopic inspection was carried out with white light and then repeated with blue light after the injection of 2 ml of 10% sodium fluoresceinate. Fluorescence was graded visually. Seventy six pairs of biopsy specimens were obtained. Of 38 specimens from non fluorescent areas, histological appearances were normal in 34. Slight inflammation was observed in three biopsy specimens, and in one there was evidence of tumour even though the specimen was obtained some distance from the primary tumour. Of 38 biopsy specimens from fluorescent areas, histological examination showed appearances of moderate inflammation in 10, severe inflammation in 10, tuberculosis in one, and carcinoma in 11. In six instances histological appearances were normal. Five normal subjects who were smokers were also examined by the same technique. Appearances of metaplasia were found more often in areas showing fluorescence than in areas not showing fluorescence. Bronchial fluorescence is considered to be related to alteration in vascularity and is not specific for carcinoma. The most fluorescent areas are generally the most pathological and visible tumour is very fluorescent, but moderate degrees of fluorescence are difficult to interpret. Biopsy of every fluorescent area seems excessive.