Evaluation Study On the Correlation Between Magnification Endoscopy with Narrow Band Imaging and Histology in the Diagnosis of Early Gastric Cancer

Abstract

Background: Gastric cancer is still the leading cause of death worldwide, therefore it is essential to detect it in an early stage for curative therapy. Widespread use of endoscopy has yielded in a high detection rate of early gastric cancer (EGC), however there are cases that are difficult to distinguish between cancer and erosion or gastritis. For EGC with subtle change of mucosal elevation or depression and color, the detection is often difficult and the chance of taking a biopsy may be little. Narrow-band imaging with magnification endoscopy (NBI-ME) provides information of fine mucosal pattern (FMP) and microvascular pattern (MVP) of the gastric mucosa. To seize the surface changes of EGC with NBI-ME may have a possibility of diagnostic improvement. Aim: To clarify the characteristics of surface changes of EGC observed by NBI-ME. Patients and Methods: From November 2007 to October 2008, 166 cases of EGC were observed by NBI-ME and were consecutively enrolled. Characters of FMP and MVP were recorded and compared to macroscopic and histological type. Pathological assessment of the lesion was done by specimen obtained by endoscopic resection or surgery. Results: For macroscopically elevated lesions, FMP were classified in tubular/small/irregular: 10/11/18 cases. For depressed lesions, FMP were classified in small/disappeared/unclassified: 73/50/20 cases. Among differentiated type EGC, 79 small type FMP was observed in 154 cases (51%). and 7 irregular type FMP was observed in 13 cases (54%) of undifferentiated EGC. MVP was classified in fine network/corkscrewed/disappeared/unclassified: 6/11/18/12 cases for elevated EGC, 28/35/40/28 cases for depressed type EGC, 36/35/59/37 cases for differentiated type EGC. For undifferentiated EGC, there were no cases of fine network pattern and 9 cases (70%) of corkscrewed pattern were observed. Conclusion: Small type FMP was more often observed among depressed type EGC, however there were no tendency in MVP according to macrosopic findings. Although differentiated type cancer may show several types of MVP, undifferentiated cancer did not show fine network pattern but often showed corkscrewed pattern. At present, irregular patterns of mucosal and vascular structure can be easily observed by NBI-ME, but it is difficult to achieve a simple classification for diagnosis.