術前に診断しえた微小胃カルチノイドの1例

Preoperatively Diagnosed Minute Carcinoid Tumor of the Stomach, Report of a Case

要旨　患者は33歳の女性で，胃部膨満感で来院，内視鏡検査で体上部前壁に急性潰瘍，体中部大彎に径4mmの発赤を伴う小隆起性病変を認め，隆起部からの生検で胃カルチノイドと診断された．切除胃において粘膜下層に充実胞巣状，一部分索状に配列する腫瘍が認められた．胃底腺領域にendocrine cell micronest（ECM）の多発がみられたが，カルチノイドは単発であった．術前，血中ガストリンとグルカゴンが高値を示したが，PAP法による免疫組織化学的検索ではガストリン，グルカゴン，いずれも陰性であり，術後血中ガストリンは低値となったが血中グルカゴンは依然高値を示し，本腫瘍がこれらのホルモンを産生したとは考えにくかった．

　The patient was a 33-year-old woman with a chief complaint of epigastric distress. Gastroscopy disclosed an ulcer on the anterior wall of the upper body and a small reddish mucosal upheaval (diameter 4 mm) on the greater curvature of the middle body. Biopsy specimen from the upheaval lesion revealed typical features of carcinoid tumor. In the laboratory findings, serum gastrin and glucagon levels were high at 169 pg/ml and 341 pg/ml. respectively. Glucose tolerances was normal and gastric juice was hypochlorhydria. A subtotal gas-trectomy was performed. Histologically, the tumor con-sisting of cells arranged in nests and trabeculae was present in the submucosal layer in the corpus of the stomach. Grimelius staining was positive but, using the immunohistochemical method, tests to detect gastrin, glucagon, serotonin, and somatostatin respectively in the cells showed negative results. Multiple endocrine cell micronests (ECMs) were found in the fundic gland area but there was no more neoplastic carcinoid. After the operation serum gastrin level returned to within normal range but serum glucagon level remained at 242 pg/ml. These findings showed that hyperglucagonemia was not caused by this carcinoid tumor.