胃癌ESD後の追加切除例の臨床病理学的検討と経過・予後

Clinical Outcomes of Early Gastric Cancer Treated by Additional Gastrectomy after Non-curative Endoscopic Submucosal Dissection

要旨　早期胃癌2,295例に対してESDを施行した後の病理組織学的診断にて，ESD適応外病変と診断された271例のうち97例に追加外科切除を行った．追加外科切除症例の臨床病理学的検討では8例にリンパ節転移が認められ，肉眼型分類における非陥凹型（隆起型・平坦型）と静脈侵襲陽性はリンパ節転移の危険因子であった．追加外科切除後の経過では血行性転移再発を3例に認め，うち1例では腹部大動脈周囲リンパ節にも転移がみられた．再発を来した3例は全例原病死した．ESD後に適応外病変と診断された粘膜下層浸潤（T1b）胃癌79例に追加外科切除を行った結果，76例（96％）には再発を認めなかった．T1b胃癌においてもESDを先行して適応外病変であった場合には追加胃切除を行うという治療戦略は，一次治療として外科的胃切除を選択するのと同程度の治療効果が期待できる．

　A total of 2,295 patients with early gastric cancer were treated by ESD（endoscopic submucosal dissection）at our hospital from January 2000 to December 2013. Non-curative resection was observed in 271 patients ; all of them were recommended to be treated by additional gastrectomy, but only 97 patients underwent additional gastrectomy. Pathological analysis revealed lymph node metastases in 8 patients. Non-depressed type（elevated or flat type）, in macroscopic type classification, and venous invasion were the risk factors for lymph node metastasis.

　Metachronous distant metastases were detected in 3 patients, and among them, para-abdominal aortic lymph node metastasis was detected in one. All the 3 patients with recurrence died of gastric cancer. Seventy-six of 79（96％）patients with T1b undergoing additional gastrectomy survived without recurrence. Therefore, additional gastrectomy following non-curative ESD was a useful strategy for early T1b gastric cancer and surgical gastrectomy.