早期胃癌に対する機能温存手術

Function-preserving Surgery for Early Gastric Cancer

要旨　早期胃癌患者の増加に伴い，治療後の生活の質がより重視される時代に入った．手術手技の進歩に伴い，従来からの幽門側胃切除術，胃全摘術の他に，様々な縮小手術が行われている．早期胃癌の約10％を占めるリンパ節転移陽性例をある程度の精度で除外できれば，内視鏡的粘膜切除（EMR）/粘膜下層剝離術（ESD）や機能温存手術（胃部分切除や幽門保存胃切除術）の適応は飛躍的に増加すると考えられる．そのためには，より精度の高いリンパ節転移診断法が求められる．リンパ流域の検索や術中センチネルリンパ節生検の検証と標準化が進み，近い将来，日常臨床に取り入れられることを期待したい．内視鏡治療と標準手術の間に位置づけられる機能温存手術を概説する．

　With increasing numbers of patients diagnosed with early-stage cancer and improvements in postoperative survival periods, quality of life after gastric surgery has become a matter of common interest among surgeons, patients, and society. Post-gastrectomy disturbances such as dumping syndrome, alkaline reflux esophago-gastritis, and reduced food intake due to small gastric volume are unpleasant sequelae in patients undergoing distal gastrectomy. Pylorus-preserving gastrectomy as a means of avoiding dumping syndrome and duodenal fluid regurgitation is a current topic of interest. To preserve gastric volume and improve quality of life, segmental gastrectomy with lymphadenectomy using sentinel node analysis has recently been introduced for early gastric cancer.

　We described both laparoscopic and open gastrectomies for patients with early gastric cancer which are judged as unsuitable or not indicated for endoscopic submucosal dissection (ESD). Minimally invasive function-preserving gastrectomy should be regarded as the bridge between ESD and conventional gastrectomy for early gastric cancer. If the advantages of these procedures can be confirmed in multicenter randomized control studies with long-term outcomes, they will receive wide acceptance and global use.