超音波内視鏡が診断に有用であった十二指腸カルチノイドの1例

Carcinoid Tumor of the Duodenal Bulb, Report of a Case

要旨　患者は68歳，男性．ドック検診の胃透視で十二指腸球部に隆起性病変を指摘され入院した．胃十二指腸X線透視では十二指腸前壁に直径15mmの粘膜下腫瘍様の隆起性病変を認めた．上部消化管内視鏡検査ではカルチノイドが疑われたが，初回生検でカルチノイドの所見は得られず頂部に陥凹を伴う潰瘍を形成した．21日後の潰瘍面からの再生検でカルチノイドと確診された．上部消化管超音波内視鏡所見では粘膜下層に限局した低エコー層として描出され，所属リンパ節の腫脹は認められなかった．また肝臓などへの転移も認められず遠位広範囲胃切除術が施行された．EUSはカルチノイドの術前検査として有用な検査法であると考えられた．

　A 68-year-old man was referred to our hospital because of a protruded lesion in the duodenal bulb suspected at a health-screening program. The first upper GI endoscopy revealed an elevated lesion covered with normal-appearing mucosa in the anterior wall of the duodenal bulb; palpation with forceps revealed elastic firm consistency. Endoscopic biopsy, however, failed to lead to a specific histological diagnosis. The second upper GI endoscopy, performed three weeks later, disclosed the formation of an ulcer at the site of previous biopsy; another biopsy from the ulcerated area led to the histological diagnosis of carcinoid tumor. Upper GI series revealed a hemispherical lesion measuring 15 mm in diameter. Endoscopic ultrasonography (EUS) demonstrated that the tumor was located in the submucosa, and that the proper muscle layer was kept intact; lymph node was not enlarged. Operation was performed, and the histological examination of the specimen confirmed the preoperative diagnosis by EUS.

　Application of EUS for carcinoid tumor of the duodenum has not been so far reported. EUS is, however, expected to be a reliable method in the diagnosis of the extent of carcinoid tumor, contributing to the determination of operative procedure.