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Diagnosis and Treatment of Gastric Carcinoid

要旨　消化管カルチノイドは，粘膜下腫瘍の様相を伴う隆起性病変で，被覆上皮の頂部は発赤，星芒状陥凹，不整形潰瘍などを認めることが多い．胃カルチノイドは基礎疾患との関係が注目され，I型（萎縮性胃炎と高ガストリン血症に伴う），II型（多発性内分泌腺腫症ないしZollinger-Ellison症候群に伴う），およびIII型（高ガストリン血症を伴わない）に分類されている．胃体部に好発し，I型およびII型では小型の腫瘍がしばしば多発性に発生する．I型とII型の背景粘膜には，内分泌細胞の過形成や微小胞巣が認められ，前者では胃体部優位の萎縮性胃炎，後者では胃粘膜上皮の肥厚を伴う．したがって，胃カルチノイドの臨床診断に際しては，腫瘍のX線・内視鏡所見に加え，背景粘膜と血清ガストリン値を評価する必要がある．

　Carcinoid tumors of the gastrointestinal tract are polypoid lesions recognized as submucosal tumors. The tumors are frequently accompanied by redness, irregularly shaped depression, or ulceration on the top. Possible association between the development of gastric carcinoids and other underlying conditions has been investigated. Nowadays, gastric carcinoids are classified into three types : Type I ; gastric carcinoids associated with hypergastrinemia and atrophic gastritis, Type II ; those associated with multiple endocrine neoplasia type1and/or Zollinger-Ellison syndrome and, Type III ; those occurring in subjects with normogastrinemia. The tumors occur predominantly in the gastric body. Those of type I and type II, are small in size, and are multiple. In type I and type II tumors, the background gastric mucosa contains endocrine cell hyperplasia or nodules. The background mucosa is atrophied in the former type, and is hypertrophied in the latter. It is thus suggested that background mucosa and serum gastrin level should be evaluated for the diagnosis and treatment of gastric carcinoid.

　1) Division of Gastroenterology, Fukuoka Red Cross Hospital, Fukuoka, Japan

　2) Department of Medicine and Clinical Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan