Barrett食道癌の内視鏡診断―IEEを用いた拾い上げ診断のポイント

Utility of Narrow Band Imaging Magnified Endoscopy for Detecting and Diagnosing Barrett's Adenocarcinoma

要旨　表在性Barrett腺癌の早期発見において，まずは通常内視鏡で発赤・凹凸不整の所見を見落とさないことが重要である．次に拡大内視鏡を併用したNBI観察を行う際には，最初に中等度拡大観察でBarrett粘膜・食道全体を観察する．腫瘍を疑う病変を認めた際，その辺縁から中心へと病変全体を観察し，粘膜模様の異常所見（不整な粘膜模様や粘膜模様の微小化・消失）の有無とその領域性（demarcation lineの有無）について評価する．その後，拡大率を上げて，不整な微小血管像（拡張と形状不均一）の有無を評価する．この診断手順を応用すれば，NBI拡大内視鏡は拾い上げ診断に加え，内視鏡的切除術前の腫瘍範囲診断においても強力な診断ツールとなりえる．

　NBIME（narrow-band imaging magnified endoscopy）, one of the image-enhanced endoscopy modes, has been reported as a useful tool for detecting and diagnosing Barrett's esophagus and adenocarcinoma. It is primarily important not to miss redness or rough surface in conventional white light endoscopy for detecting superficial Barrett's adenocarcinoma. In NBIME, the half-zoom mode should be recommended for observing the whole of Barrett's esophageal surface and in order to find abnormal mucosal pattern surrounded by a demarcation line. Then, by increasing the magnification power, irregularities of microvessels should be evaluated if you find a demarcated abnormal mucosal pattern. NBIME can be a very useful diagnostic tool when estimating tumor extent before endoscopic resection. We describe two cases of Barrett's adenocarcinoma at an early stage which NBIME allowed us to detect and diagnose the tumor extent exactly. Clinical utility of NBIME for Barrett's adenocarcinoma is discussed in this manuscript.