経鼻内視鏡を用いた胃癌スクリーニング検査で発見された微小胃癌の2例

Two Patients with Minute Gastric Carcinomas Detected in Screening for Gastric Carcinoma using a Transnasal Endoscope

要旨　〔症例1〕は40歳代，男性．経鼻内視鏡を用いた人間ドックの胃癌スクリーニング検査にて前庭部大彎に0-IIc病変を認めた．生検にて高分化型腺癌の診断で，内視鏡的粘膜下層剝離術（ESD）を行い，病理診断はType 0-IIc，tub1，5×5mm，pT1a（M）の微小胃癌であった．〔症例2〕は40歳代，男性．経鼻内視鏡を用いた人間ドックの胃癌スクリーニング検査で胃角部前壁に0-IIa＋IIc様病変を認め，生検で高分化型腺癌の診断でESDを行い，病理診断はType 0-IIc，tub1，4×3mm，pT1a（M）の微小胃癌であった．経鼻内視鏡を用いた胃癌スクリーニングにおいて，経鼻内視鏡の特徴を十分理解し，基本に忠実で丁寧な観察を行うことで，微小胃癌の発見も可能であり，通常内視鏡検査とほぼ同等の診断精度を得ることができると考えられる．

　Patient 1 : A man in his forties underwent a complete medical checkup, in which screening for gastric carcinoma using a transnasal endoscope revealed a type 2c lesion in the greater curvature of the antrum. A diagnosis of well-differentiated adenocarcinoma was made based on biopsy. ESD（endoscopic submucosal dissection）was performed, and a pathological diagnosis of minute gastric carcinoma［Type 0-IIc, tub 1, 5×5mm, pT1a（M）］was made.

　Patient 2 : A man in his forties underwent a complete medical checkup, in which screening for gastric carcinoma using a transnasal endoscope revealed aIIa＋IIc-like lesion in the anterior wall of the angle. A diagnosis of well-differentiated adenocarcinoma was made based on biopsy. ESD was performed, and a pathological diagnosis of minute gastric carcinoma［Type 0-IIc, tub1, 4×3mm, pT1a（M）］was made.

　It is considered that screening for gastric carcinoma using a transnasal endoscope, with a full understanding of its characteristics and careful observation, can detect minute gastric carcinoma, and yield a diagnostic performance equivalent to that of normal endoscopy.