切除材料からみた早期胃癌内視鏡的切除の適応拡大の可能性―多施設集計による検討

Curative Endoscopic Resection of Early Gastric Cancer: The Possibility of Extending Its Indications

要旨　早期胃癌の内視鏡的絶対治癒切除法の条件は，1回の切除術で癌病巣を完全切除することに加え，リンパ節転移のないことが必須である．この条件を考慮して内視鏡的治癒切除法の適応拡大について多施設集計を含め検討した．リンパ節転移の面からみると分化型m癌のうち30mm以内のⅡa＋Ⅱc，30mm以内のⅡbおよびⅡc・Ul（－）群，また低分化型m癌でも30mm以内のⅡbおよびⅡc・Ul（－）群ではn（－）であり，将来の技術面での改良によって適応拡大の可能性が示唆される．このためには切除術式の改良に加え，ワイヤー・ループの絞扼時の滑り止めの工夫や，病巣の正面視のために前方斜視型の利用，側視鏡の開発など内視鏡機器の改良も重要な課題である．

　For successful curative endoscopic treatment of early gastric cancer, it is essential that the primary lesion should be completely removed and there should be no lymph node metastasis, On the basis of these requirements, to assess the posibility of extending indications for curative endoscopic resection of early gastric cancer, the resected specimen was examined histologically. Patients with early gastric cancer from multiple institution were enrolled in this study. No lymph node metastasis was confirmed in the following patients; 1) type Ⅱa＋Ⅱc, and type Ⅱb and Ⅱc with Ul (-) well differentiated mucosal cancer less than 30 mm in size, 2) type Ⅱb and with Ul (-) poorly differentiated mucosal cancer less than 30 mm in size. These findings suggest that complete endoscopic resection can be applied to a larger proportion of early gastric cancer patients in the future as techniques are improved. In addition to the improvement of resecting procedures, better endoscopic instruments needs to be developed, including modification of the wire-loop stopper to prevent slipping while tightening the loop, and development of the frontaloblique-viewing and side-viewing endoscopes.