Evaluation of narrow-banding imaging endoscopy in the diagnosis of early squamous esophageal cancer and precancerous lesions

Objective To evaluate the narrow-banding imaging （NBI） in the diagnosis of early esophageal squamous cancer and precancerous lesions. Methods The esophagus was examined with white-light and NBI endoscopy respectively. Subsequently, abnormal appearance of intrapapillary capillary loop （IPCL） was carefully inspected by NBI combined with magnifying endoscopy. Finally, 1.2% Lugoul＇s iodine solution was used to stain the mucosal surface. For each suspected lesion, the location, classification and technique used were recorded. Biopsies were taken from each abnormal part. The pathologic diagnosis was considered as golden standard for all lesions, thus the grade of NBI, the type of IPCL and the grade of Lugoul＇s iodine staining in lesions were compared with pathologic features. Results （ 1 ） One hundred and four lesions were detected in 72 patients with all techniques above. With white-light endoscopy, the incidence rate of early esophageal squamous cancer and precancerous lesions detected by senior endoscopist and junior endoscopist was 82.7% （86/104） and 70. 2% （73/107）, respectively. With NBI endoscopy and iodine staining, the incidence rate detected by senior or junior endoscopists was the same, 86. 5% （90/104） and 100. 0%, respectively. （2） For iodine staining, 100% of high grade intraepithelial neoplasia（HGIN） were positive, including 83.0% （39/47） Grade Ⅰ, and 17.0% （ 8/47 ） Grade Ⅱ / Ⅲ. 100% of low grade intraepithelial neoplasia （ LGIN ） were positive, including 12. 8% （ 6/47 ） Grade Ⅰ and 87. 2% （ 41/47 ） Grade Ⅱ/Ⅲ. （3）Using NBI, 91.5% （43/47）of HGIN were positive, including 69. 8% （30/43） Grade Ⅰ and 30. 2% （ 13/43 ） Grade Ⅱ / Ⅲ. 57.4% （ 27/47 ） of LGIN were positive, including 14. 8% （ 4/27 ） Grade Ⅰ and 85. 2% （23/27） Grade Ⅱ/Ⅲ. （4） In appearance of IPCL, 93. 6% （44/47） of HGIN were abnormal, including 88. 6% （39/44） Type Ⅳ/Ⅴ and 11.4% （ 5/44 ） Type Ⅱ / Ⅲ. 76.6% （ 36/47 ） of LGIN were abnormal, including 22. 2% （8/36） TypeⅣ/Ⅴ and 77. 8% （28/36） Type Ⅱ / Ⅲ. Conclusion Compared with white-light endoscopy, beth NBI endoscopy and iodine staining can identify early esophageal squamous cancer and precancerous lesions. In the diagnostic accuracy of HGIN, there was no difference between the classification of IPCL and iodine staining. NBI is a novel and valuable technique in the diagnosis of early esophageal squamous cancer and precancerous lesions. Key words: Esophageal neoplasms;  Endoscopy, digestive system;  Narrow-banding imaging;  Capillaries