大腸内視鏡治療における拡大観察応用の最先端―計画的分割切除における拡大観察の有用性

Usefulness of Endoscopic Magnifying Observation in Intended Piece-meal Resection

要旨　粘膜下層（sm）に浸潤した部を分断して分割切除してしまうと組織学的転移危険因子の評価は不可能に近い．また，分割切除標本では側方切除断端における腫瘍組織の有無の組織学的評価もかなり難しい．したがって，分割切除を行う場合は切除前にsmに浅く浸潤している（sm-s）可能性のある部位を診断し同部を一括して十分に切除すること（計画的分割切除）と切除時内視鏡的に腫瘍遺残のないことを確認することが必要である．sm-sの診断には拡大観察による軽度不整VI pitの存在の有無が有用な指標であり，腫瘍遺残の確認には拡大観察による腫瘍性pit（IIIs，IIIL，IV，V型pit）残存の有無が有用な指標である．

　It is almost impossible to evaluate the histologic factors of metastasis in cases in which the submucosal invasive area has been cut. In addition, histologic evaluation of lateral margin curability is more difficult in specimens obtained by piece-meal resection. Consequently, in cases of piece-meal resection, it is mandatory to diagnose the precise shallow submucosal invasion (sm-s) at the site prior to the procedure, and to have well scheduled piece-meal resection so as to include the total sm-s site area, followed by careful endoscopic confirmation that there is no residual lesion.

　It is useful for diagnosis of sm-s invasion to perform endoscopic magnifying observation of VI pit pattern, and for the residual lesion to observe the IIIs, IIIL, IV, and V pit patterns (neoplastic pits).