A型胃炎に合併した多発性胃カルチノイドの1例

Multiple Gastric Carcinoids with Type A Gastritis, Report of a Case

要旨　患者は39歳，男性．検診で胃ポリープを指摘され精査目的にて人院．X線・内視鏡検査で胃体部を中心に1cm以下の小ポリープの多発が認められ，生検にてカルチノイドとの診断を得た．内分泌学的検査において高ガストリン血症（2,400pg/ml）がみられ，24時間胃内pHモニタリングでは昼夜を問わず持続的なpH上昇が認められたことから，A型胃炎に伴う多発性胃カルチノイドとの診断にて胃全摘術およびリンパ節郭清を行った．組織学的には，胃底腺の著明な萎縮をみる粘膜を背景として，カルチノイド腫瘍および内分泌細胞微小胞巣の増生が認められたことより，高ガストリン血症のtrophic actionによりenterochromaffin-like cellの過形成，腫瘍化が起きた症例であると考えられた．

　A 39-year-old male was admitted for further evaluation of multiple elevated lesions in the stomach which were pointed out in a periodic health examination. Gastrofiberscopy revealed multiple small elevated lesions in the gastric corpus, and biopsy specimens obtained from 5 elevated lesions showed histologically that they were carcinoid. Remarkable hypergastrinemia (2,400pg/ml) was observed, whereas urine 5-HIAA and serum serotonin level were within normal range. Total gastrectomy was performed and 10 polypoid lesions were macroscopically observed in the resected stomach. Eleven carcinoids and many endocrine cell micronests (ECMs) were observed microscopically seen in the severely atrophic fundic mucosa (consistent with type A gastritis) of the stomach. These findings suggest that the multiple carcinoids and ECMs in this case were hyperplasia or neoplasia of enterochromaffin-like cells due to hypergastrinemia.