The Usefulness of Observing a Fine Surface Structure Using Magnifying Endoscopy in Determining the Range of Early Gastric Cancer

Abstract

Introduction: The range diagnosis before endscopic treatment is important to obtain a good treatment outcome in early gastric cancer. The purpose of our study is to investigate the usefulness of observing a fine surface structure using magnifying endocopy in determining the range of early gastric cancer. Aims and Methods: We studied 257cases of gastric epithelial tumor with 265 lesions which were treated with ESD(Endscopic Submucosal Dissection) after being observed through a magnifying endoscope. We investigated 1) comparisons between the fine surface structures using magnifying endscope and clinical pathological findings and 2) diagnosabilities of the conventional endoscopic and magnifying endscopic groups to determine the range of gastric cancer. The surface structures were classified into the following three groups: TP (the tubular pattern with irregular microstructure), PP(the papillary pattern with irregular microstructure) and DP(the destructive pattern). Also, TP was subclassified into comparatively large tublar TP-L and TP-S of small tubular . Results: 1)The comparison between the fine surface structures and pathological findings were as follows: For TP, adenoma was found in 23 out of 25 cases(92.0%), mucosal cancer in 112 out of 140 cases (80.0%) . For PP, mucosal cancer in 20 out of 140 cases (14.3%). For DP, musocal cancer was found in 8 out of 140cases (5.7%) and submucosal cancer in 17 out of 28 cases (60.0%) (p<0.001). Thus, DP was significantly distinguishable in submucosal cancer, while TP was mainly observed in adenoma and mucosal cancer. About the fine surface structures, microscopic configuration and mucous phenotype, TP-S was observed in depressed type lesions (95.7%) and mostly had gastric type mucous expression (43.5%). TP-L was seen in protruded type lesions (100%) and mostly had intrestinal type mucous expression (78.6%). DP was seen in any depressed type lesions (100%). 2) We carried out the range diagnosis of gastric cancer using the fine surface structures classified according to the macroscopic configuration and the histological type. Of those using a conventional endoscope, the cases of lateral margin (-) totaled 63, or 87.5%, with three cases of obscure lateral margin and six cases of lateral margin (+). The diagnosability of magnifying endoscopy significantly improved with the cases of lateral margin (-) totaling 191, or 99.0% (p<0.001). Conclusion: The diagnosis of the range of early gastric cancer by observing a fine surface structure obtained through magnifying endscopy is useful for curative endscopic treatment.