大腸sm癌の細分類と内視鏡的摘除の適応

Degree of Submucosal Invasion of Colorectal Carcinoma and Applicability of Endoscopic Resection

要旨　大腸sm癌120例をsm浸潤度別に分類し，内視鏡的摘除の適応について考察した．有茎型では，内視鏡的摘除は90.9％であり，頭部の大きさに関係なく(茎の太さ20mm以下)適応と考えられる．亜有茎・無茎型は20mm以下で71.0％であり，そのうちの77.3％がsm₂であった．また表面型では20mm以下で50.0％であるが，そのうちの50.0％がsm₂であった．肉眼像では亜有茎・無茎型では不均一，外反，陥凹+外反を，表面型では外反，陥凹+外反を示すものではsm₂以深が多く，内視鏡的摘除のみで治療を完了する率は低い．よって内視鏡的治療を行う前には，詳細な観察による深達度診断を行い，治療法の選択を考慮する必要があると思われる．

　Classifying 120 cases of sm carcinoma according to the degree of sm invasion, we considered the applicability of endoscopic therapy. We were able to resect endoscopically 90.9% of all pedunculated lesions, and we thought it appropriate to use endoscopic therapy to deal with pedunculated lesions (stalk of 20mm or below), regardless of the size of the head. We were able to resect endoscopically 71.0% of all subpedunculated and sessile lesions, but 77.3% of these were sm₂ invasions.We were able to resect endoscopically 50.0% of all superficial lesions, but 50.0% of these were sm₂ or sm₃invasions. Macroscopically, subpedunculated and sessile sm carcinomas showing asymmetry, depression, or depression + over-hanging of normal mucosa were sm₂ or sm₃ in many cases. Meanwhile, superficial sm carcinomas showing over-hanging of normal mucosa and depression+over-hanging of normal mucosa were sm₂ and sm₃ in many cases. So in case of macroscopic findings as mentioned above, the rate of completion of treatment by endoscopic resection alone is low. Therefore, before performing endoscopic treatment, the depth of the carcinoma should be carefully observed so that the best treatment method can be selected.