拡大内視鏡所見からみた胃分化型SM1癌の診断

Diagnosis of Intestinal-type Gastric Cancer with SM1 Invasion by Magnifying Endoscopic Findings

要旨　分化型早期胃癌の拡大内視鏡像を術後深達度診断別に解析し，SM1癌の特徴について検討した．術後病理診断が得られた陥凹型病変60例を対象とした．微細表面構造では，SM癌で有意に無構造領域の出現を認め，M癌とSM1癌の比較でも有意差を認めた（p＜0.05）．また，微細血管構造については分化型癌に特徴的な微細網目状血管（fine network pattern）と孤立性血管（solitary pattern）の混在がSM癌では多かった．SM1癌の無構造領域を詳細に検討すると，融合状の腺管構造と伸展したあるいは樹枝状血管が認められ，拡大内視鏡によるSM1癌診断の指標となると思われた．また，本検討においてはSM1とSM2癌では微細表面構造と微細血管構造に違いを認めなかった．

　In order to determine the characteristics of SM1 invasive cancer, we analyzed magnifying endoscopic findings of intestinal-type early-stage gastric cancer according to postoperative diagnosis of invasion depth.

　Sixty cases of depressed type early gastric cancer for which postoperative diagnosis was obtained were investigated. In the image of the surface microstructure, a nonstructural pattern was observed frequently in SM cancer, and there was a significant difference in frequencies of its appearance between m cancer and SM1 cancer (p＜0.05). Moreover, in images of the microvascular structure, a combination of a fine network pattern and an isolated pattern was observed frequently in sm cancer. Detailed observation of the nonstructural pattern in SM1 cancer revealed a fused pattern of tubular structures and abnormal microvessels such as stretched type and branched type. These may be effective as an indicator by magnifying endoscopy of SM1 cancer. However, the results of this study revealed no obvious differences between SM1 cancer and SM2 cancer in surface microstructure or microvascular pattern.