早期胃癌に対するNBI拡大内視鏡

We have described the surface glandular structure and microvessels in differentiated early gastric cancer observed by narrow-band imaging with magnifying endoscopy (NBI-ME), such as papillary or granular structure in an intralobular loop pattern or pit structure in fine network pattern. However, it was uncertain why the NBI-ME findings of differentiated-type carcinomas are divided into two main patterns. We investigated the significance of the mucin phenotype in the morphogenetic difference, and suggested mucin phenotype of differentiated early gastric cancer might involve morphogenic differences between papillary and pit structures visualized by NBI-ME. Moreover, we analyzed 541 early gastric cancers from patients who underwent endoscopic submucosal dissection (ESD) after detailed observation by NBI-ME. By conventional endoscopy, it was difficult to make a correct determination of IIb spreading of differentiated-type adenocarcinomas with gastric mucin phenotype. The findings of NBI-ME were loop-form microvessels in each small granular structure. The margin of these lesions could be visualized by the microvascular and fine glandular architecture different from those of the surround non-neoplastic mucosa.