Endoscopic ultraviolet-induced autofluorescence spectroscopy of the esophagus: Tissue characterization and potential for early cancer diagnosis

Background and Study Aims: Endoscopic identification of dysplasia and early carcinoma of the esophagus is difficult and is currently done through rand om pinch biopsies. This study assesses the potential of ultraviolet-induced autofluorescence spectroscopy for early diagnosis with special focus on Ba rrett's esophagus, Patients and Methods: Measurements were performed on 24 patients using 330 nm light excitation. The determination of the spectral distribution typical of each histological tissue type was done using three fluorescence intensi ty ratios: R-1 = I-390nm/I-450nm; R-2 = I-550nm/I-450nm; R-3 = I-390nm/I-55 0nm. Results: The spectral distribution of normal esophageal mucosa and speciali zed columnar Barrett's mucosa were similar. A strong modification of the sp ectral distribution was observed for high grade dysplasia and intramucosal carcinoma. Statistical analysis indicated that the spectral shape modificat ion associated with neoplastic transformation was greater than intra- and i nterpatient spectral variations. These results allow the determination of d iscriminating criteria based on ratios R-1 and R-3. Using ratio R-3, the sp ectroscopy-based diagnosis differentiated neoplastic tissue from normal eso phageal mucosa and specialized columnar Barrett's mucosa with a sensitivity and specificity of 86% and 95%, respectively, Conclusions: The use of ultraviolet autofluorescence spectroscopy should im prove the diagnostic yield of standard endoscopy in patients with Barrett's esophagus.