表在型Barrett食道癌の側方進展範囲診断

Endoscopic Diagnosis of Superficial Barrett's Esophageal Adenocarcinoma

要旨●2000年1月〜2016年3月までの間に，当センターにてESDを施行した49例，63病変のBarrett食道表在癌を対象とし，SSBE群とLSBE群に分けて術前の範囲診断正診率を検討した．SSBE 40例，LSBE 9例で，肉眼型はSSBEでは隆起型が，LSBE群では平坦陥凹型を多く認めた．0-IIb合併率はSSBEでは51％（21/41），LSBEでは89％（8/9）であった．腫瘍長径中央値はSSBEで13（4〜116）mm，LSBEで45（2〜96）mmであった（p<0.01）．全例に拡大内視鏡検査にて表面構造，血管構造をもとにマーキングを施行し，癌がこの範囲にとどまっている場合を正診とした．結果：SSBEに対する正診率はWLI：56％，拡大内視鏡検査96％．LSBEではWLI：7％（1/15），拡大内視鏡検査100％と有意差を認めた（p＝0.01）．扁平上皮下進展を示した癌はSSBEで60％（29/48），LSBEで27％（4/15）で，進展距離中央値は，それぞれ4（1〜12）mm，5（1〜20）mmであった．上皮下進展を示唆する所見の出現率は色調変化88％（29/33），厚み36％（12/33），異常血管88％（29/33），小孔42％（14/33）であった．拡大内視鏡検査はBarrett食道表在癌の範囲診断に有用だが，それでも範囲診断が困難な症例があり，SSBEでは扁平上皮下進展，LSBEでは随伴0-IIbの存在に配慮すべきである．

　A retrospective study regarding the diagnosis of lateral extension of Barrett's EAC（esophageal adenocarcinoma）was conducted. Sixty-three EAC cases from 49 patients treated by ESD from 2000 to 2015 in Saku Central Hospital were enrolled in this retrospective study. The numbers of EAC cases undergoing LSBE and SSBE were 48 and 15, respectively. Median tumor sizes were 13（4〜116）mm and 45（2〜96）mm, respectively, for SSBE and LSBE（p<0.01）. All lesions were diagnosed and marked by ME（magnified endoscopy）. The diagnosis was judged as correct when the cancer was confined to the markings. Results： The accuracy for EAC diagnosis on SSBE using WLI（white-light image）and ME was 56% and 96%, respectively（p<0.01）, and that on LSBE was 7% and 100%, respectively（p<0.01）. The rate of SEI（subsquamous cell epithelial invasion）for SSBE and LSBE was 60% and 27%, respectively（p＝0.47）. The following endoscopic findings of redness, thickness, irregular vessels, and small holes, were observed in 88%, 36%, 88%, and 42% cases, respectively. In conclusion, ME was useful for the diagnosis of lateral extension of EAC, not only on SSBE but also on LSBE.