主として食道内発育を示した隆起型食道胃接合部腺癌の1例

0-Ⅰ Type Adenocarcinoma at the Esophagogastric Junction, Most of which was Located in the Esophageal Side, Report of a Case

要旨　患者は54歳，男性．51歳時より胃十二指腸潰瘍の診断治療を受け，毎年人間ドックで内視鏡検査を行っていたが，心窩部痛にて行った内視鏡検査で食道病変を指摘された．上部消化管造影にて噴門部前壁に大きさ2.2×1.5cmの隆起性病変があり，中央にバリウム斑を認めT1b（sm3）と診断．また内視鏡にて食道胃粘膜接合部に同様の0-Ⅰpl型T1b（sm3）の食道癌と診断．生検にて腺癌であった．全身状態良好にて手術を行い，高分化型管状腺癌，pT1b（sm3）N0M0 pStage I，ly₀，v₂の病理組織診断であった．食道胃接合部癌は，生理的狭窄や複雑な形態からスクリーニングで見落とされやすく，他部位の胃癌に比し表在癌の頻度が低い．隆起型を呈した高分化型腺癌で，大きさ2.0cmと小さい割に既に粘膜下層深部に浸潤している比較的特徴的な症例であった．明らかなBarrett上皮，食道腺由来の組織学的所見はなく，胃噴門腺に癌の進展がみられ，胃噴門腺由来の可能性があるが，病変の4/5は食道側にあり，発生母地の特定は困難であった．

　A 54-year-old male was admitted to our hospital because of an abnormality at the esophagogastric junction. He had been suffering from epigastric pain due to gastroduodenal ulcers and had undergone an annual examination of the upper gastrointestinal tract for three years. The last endoscopy revealed a protruding lesion at the esophagogastric junction.

　An esophagogram revealed a small and protruding lesion with the granular surface and slight depression at the center of the lesion. Using an esophagoscopy, a type 0-I lesion was also noticed at the gastroesophageal mucosal junction. Histological studies on bite biopsy specimens revealed a well-differentiated adenocarcinoma. The depth of invasion was estimated to be submucosal (T1b : sm3) . Distal esophagectomy with proximal gastrectomy was carried out. Pathological studies on the resected specimens revealed a well differentiated adenocarcinoma, type 0-Ⅰ, pT1b (sm3) N0M0 pStage Ⅰ, ly₀, v₂. Early cancer at the esophagogastric junction is rare. The narrow space and deformities of the junction probably made the annual surveillance difficult. An adenocarcinoma at the esophagogastric junction may originate from Barrett's mucosa, the esophageal gland, the esophageal cardiac gland or the cardiac gland. In this case, there was no Barrett's mucosa. Cancer spreading into the cardiac gland suggested that the cancer originated from the cardiac gland, although 4/5 of the lesion was surrounded by squamous epithelium.