いわゆる側方発育型大腸腫瘍の治療―内視鏡的粘膜下層剝離術（ESD）

Endoscopic Treatment of Laterally Spreading Tumors

要旨

　近年の内視鏡治療技術の進歩は目覚ましく，大型腫瘍においてもESDによる治療の適応拡大が可能となった．大腸腫瘍の中で，LSTは側方への発育を主体とする腫瘍であり，内視鏡治療の良い適応と考えられるが，LST-NGの場合はsm浸潤のリスクが高くなるため，ESDによる一括切除が望ましいと考えられる．しかし，ESDは偶発症のリスクも高いため，拡大内視鏡等によるきちんとした術前診断を行ったうえで，術者や施設を限定して実施すべきものと考えられる．

　Although LST has the unique feature of tending to spread over the mucosal surface laterally, LST-NG and large-sized mixed type LST-G have relatively high risk for submocosal invasion. Therefore, en-bloc resection is necessary in cases of LST-NG and mixed type LST-G especially for large lesions exceeding 2cm. ESD is a wonderful technique, enabling us to resect the whole lesion en-bloc, and has certain merits for the treatment of large colonic tumors including LSTs. However, at present, only the expert should perform ESD since it involves risk for perforation and bleeding. Also, we have to select candidates for colonic ESD very carefully through precise preoperative diagnosis with chromoendoscopy and magnification.