早期胃癌に対する切開・剥離法の治療成績と問題点―細径スネア・フレックスナイフ

Merits and Demerits of Endoscopic Submucosal Dissection Using a Flex Knife

要旨　細径スネアを改良したフレックスナイフは，柔軟で操作性が良く，直視下で縦・横・斜めあらゆる方向に切開を進めることが可能であり，切開・剥離法を初めて行う者でも比較的扱いやすい処置具と考えられる．しかも先端がループ状になっており，長さも調整可能であるため穿孔のリスクも比較的少ないものと思われる．細径スネアやフレックスナイフを用いた切開・剥離法にて198病変の治療を行い，一括切除率は92％であった．一方，穿孔が8例(4％)，後出血が3例(1.5％)認められたが，すべて保存的に治療可能であった．切開・剥離法は，技術的難易度が高く，治療時間も長くかかるが，確実な一括切除が可能であり，根治性の評価と遺残再発の防止の点からメリットの多い治療法と考えられる．

　A flex knife, which is an improvement of the thin-type snare, is flexible and offers good maneuverability. It is possible to cut in any direction under direct vision. Therefore, it is the most suitable instrument for beginners of endoscopic submucosal dissection (ESD). Furthermore, the tip forms a loop, and its length is adjustable, which reduces the risk of perforation during ESD. Using either the thin-type snare or the flex-knife, 198 lesions were treated by ESD. The overall successful en-bloc resection rate was 92％. Though perforation was observed in 8 cases (4％)and post-operative bleeding occurred in 3 cases (1.5％), all patients recovered under conservative therapy. ESD requires skill and much time, but enables definite en-bloc resection. To obtain radical curability and prevent local recurrence from remnant tissues, ESD is the most suitable technique among those available for endoscopic resection.

　1) Department of Gastroenterology, Faculty of Medicine, the University of Tokyo, Tokyo