粘膜内癌と診断されて内視鏡的に切除されたsm癌で，追加治療によりリンパ節転移が確認された胃型の分化型腺癌の2症例

Early Gastric-type Differentiated Gastric Cancer Metastasis to the Lymph Node after EMR, Report of Two Cases

要旨　粘膜内癌の診断でEMRを施行したsm癌で，追加治療にてリンパ節転移が判明した胃型の高分化型乳頭管状腺癌の2症例．〔症例1〕65歳，男性．胃潰瘍手術後の残胃に約1.1cm大の境界不明瞭な隆起性病変を認めた．EMRにて深達度sm2，ly(＋)，v(＋)，垂直断端(＋)の診断．残胃全摘の結果，脾門リンパ節に転移を認めた．〔症例2〕77歳，男性．検診にて穹窿部後壁に約1.0cm大の隆起性病変を指摘される．EMRでsm1以深，垂直断端(＋)の診断．胃部分切除により癌の遺残(sm2，ly2，v1)と小彎リンパ節に転移．胃型分化型胃癌の中には，高い悪性度を示す症例が少なからず存在しており，治療法を慎重に選択するべきである．

　Gastric-type differentiated adenocarcinomas frequently show aggressive behavior in the early phase of cancer progression. We reported two cases of early gastric cancer in which we observed lymph node metastasis after endoscopic mucosal resection (EMR). Endoscopically, these cases were diagnosed as mucosal cancer, type 0 IIa. Histological examination revealed well differentiated papillotubular carcinoma of the gastric type, infiltrating to the submucosal layer and lymphatic vessel in EMR specimens. By additional surgical treatment, lymph node metastasis of differentiated adenocarcinoma was identified. We should be very cautions when considering the indication for EMR therapy for gastric-type differentiated adenocarcinoma.