Clinical Significance of Magnifying Endoscopy Combined with the Narrow Band Imaging System for Barrett's Esophagus

Abstract

Background: Specialized intestinal metaplasia (SIM), which distributes patchily within Barrett’s esophagus (BE), has been detected by random or four quadrant biopsy using conventional endoscopy. However, little is known about the fine mucosal structure of SIM using magnifying endoscopy. Magnifying endoscopy combined with the narrow-band imaging (NBI) system is a novel technique, which yields very clear images of not only fine mucosal patterns without using dye spray (chromoscopy) but also capillaries on the mucosal surface. Aim: We studied the diagnostic utility of SIM and adenocarcinoma in BE, using magnifying endoscopy combined with the NBI system. Method: Patients with BE were studied with magnifying endoscopy (GIFQ240Z) combined with the NBI system (Olympus Tokyo, Japan). Categorized fine mucosal patterns and capillary patterns were identified, biopsied and read by the pathologist blinded to endoscopic findings. Result: During December 2003 and August 2004, 50 patients (43 men, 7 women) with BE have been included in the study. A mean age was 64 years (range: 40-70) and a mean length of BE was 23 mm (range: 5-130). Magnifying endoscopic findings for 189 regions in BE were recorded and compared with histological findings of biopsy specimens. Fine mucosal structure was classified into 5 patterns; round or oval, straight, villus, cerebriform and irregular, and additionally capillary patterns into five categories of Type I (honeycomb-like pattern), Type II (,‡ently tortuous pattern), Type III (coil or curly-hair like pattern), Type IV (intertwining pattern with a connection), Type V (abnormal pattern showing irregular running and heterogeneous shapes). Fine mucosal patterns showing “villus” or “cerebriform” detected SIM with a sensitivity of 85% for histological findings (accuracy 58%). Type IV was peculiar to the histological region of SIM (specificity 94%, accuracy 89%). “Irregular” fine mucosal pattern and Type V capillary pattern were characteristic features of Barrett’s adenocacinoma in the early stage. Conclusion: Magnifying endoscopy combined with the NBI system provides detail images of the fine mucosal and capillary patterns in BE. In this study, we suggest that capillary patterns are more useful for the detection of SIM in BE than fine mucosal patterns. We also believe that magnifying endoscopy combined with the NBI system enables us to detect and recognize the demarcation line of Barrett’s adenocarcinoma in the early stage.