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 random pinch biopsies. This study assesses the potential of ultraviolet-induced autofluorescence spectroscopy for early diagnosis with special focus on Barrett'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 intensity ratios: R-1 = I-390nm/I-450nm; R-2 = I-550nm/I-450nm; R-3 = I-390nm/I-550nm. Results: The spectral distribution of normal esophageal mucosa and specialized columnar Barrett's mucosa were similar. A strong modification of the spectral distribution was observed for high grade dysplasia and intramucosal carcinoma. Statistical analysis indicated that the spectral shape modification associated with neoplastic transformation was greater than intra- and interpatient spectral variations. These results allow the determination of discriminating criteria based on ratios R-1 and R-3. Using ratio R-3, the spectroscopy-based diagnosis differentiated neoplastic tissue from normal esophageal 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 improve the diagnostic yield of standard endoscopy in patients with Barrett's esophagus.