Ⅱb・Ⅱcと鑑別を要する胃粘膜平坦発赤病変の拡大内視鏡像―微小血管構築所見の良悪性の鑑別における有用性を求めて

Microvacular Architecture in Flat Reddened Lesions of Gastric Mucosa Visualized by Magnified Endoscopy

要旨　内視鏡でⅡb，Ⅱcなどいわゆる胃炎類似型早期癌と鑑別が必要な平坦発赤病変の拡大観察を行い，病変境界部の粘膜上皮下の毛細血管をはじめとする微小血管構築像が，良悪性を鑑別する指標になりうるかを求めた．方法：平坦な胃粘膜発赤病変52病変を対象とした．組織学的所見から発赤胃炎群42例，発赤分化型癌群10例に分類した．内視鏡所見の内訳は，発赤胃炎群は，発赤斑31例，びらん11例，発赤分化型癌群はⅡc 9例，Ⅱb 1例であった．上部消化管拡大内視鏡の粘膜微小血管構築所見を境界明瞭所見，周辺毛細血管消失所見，異型血管増生所見に分類し胃炎群と分化型癌群における所見の頻度を求めた．結果：発赤胃炎群の71.4％は境界明瞭所見，周辺毛細血管消失所見，異型血管増生所見の3所見すべてを認めなかった．一方，発赤分化型癌群では1例の境界が不明瞭であった以外はすべての症例で上記3所見を有していた．結語：今回の検討では症例数が少なく断定はできないが，少なくとも境界明瞭所見，周辺毛細血管消失所見，異型血管増生所見のすべてを認めない平坦発赤病変については，良性の慢性胃炎の可能性が高く，拡大内視鏡観察は，平坦な発赤した癌を見つけるために行われる発赤した慢性胃炎からの無為な生検を減らしうる可能性が示唆された．

　The aim of this study was to investigate whether the differences in microvascular architecture, observed by magnifying endoscopy, could be useful findings for differentiating between focally reddened mucosa with gastritis and reddened flat gastric carcinoma. 52 focally reddened lesions in ordinary endoscopic findings were included in the study. These lesions were divided into two groups : 42 cases of reddened gastritis lesions and 10 cases of reddened differentiated carcinomas. According to the magnified endoscopic findings, the incidence of the three microvascular patterns, 1) presence of demarcation line, 2) disappearance of subepithelial capillaries and 3) proliferation of irregular microvessels, were determined for the respective groups. 71.4% of cases in the gastritis-group showed neither demarcation line, disappearance of subepithelial capillaries nor irregular microvessels. On the other hand, except for one case that failed to show the demarcation line, all the cases in the carcinoma-group demonstrated those three findings. It was suggested that if all the three findings are absent in reddened mucosal lesions viewed by magnified endoscopy, the lesion is probably gastritis rather than carcinoma. These magnified endoscopic findings might be useful for reducing biopsies that used to be unnecessarily taken from benign reddened gastritis.