Zollinger-Ellison症候群を呈した空腸原発の多発性gastrinomaの1例

Zollinger-Ellison Syndrome Caused by Multiple Jejunal Gastrinomas, Report of a Case

要旨　患者は57歳の女性で，悪心，嘔吐を主訴として来院，上部消化管検査で十二指腸球後部潰瘍がみられた．胃液検査，血清ガストリン値，セクレチン負荷テスト，Ca負荷テストよりZollinger-Ellison症候群が考えられ，腹部US，腹部CT，血管造影，PTPによる門脈採血を行ったが，腫瘍部位は確定できなかった．手術時，膵尾部は軽度腫大しTreitz靱帯から20cm肛門側空腸に指頭大の数個の腫瘍を触知したので空腸部分切除，膵尾部切除，胃全摘術を施行した，空腸腫瘍はいわゆるcarcinoidの組織像を呈し，酵素抗体PAP法で胞体内にはガストリンが証明され，腫瘍中のガストリン定量は264,444Pg/gと高値を示した．

　A 57 year-old woman was admitted to our hospital complaining of nausea and vomiting. She was diagnosed as having a duodenal ulcer in 1974 and 1982. Physical examination and routine laboratory study contributed nothing to the diagnosis. Radiologic and endoscopic examinations of the gastrointestinal tract revealed three postbulbar ulcers and vanishing of Kerckring fold. Gastric acid analysis showed that basal acid output was 19.2mEq/h and maximum acid output under histimine stimulation was 26.4mEq/h. Serum gastrin level was more than 1,200pg/ml in the fasting stage. Serum serotonin, ACTH, PTH and glucagon were not increased. Plasma gastrin levels following secretin and calcium provocation tests showed the pattern of Zollinger-Ellison syndrome. The extensive exploration before operation failed to identify a gastrin-induced lesion. During the operation, multiple tumors were palpable in the jejunum, so total gastrectomy, partial resection of jejunum and distal pancreatectomy were performed.

　In the resected ileum four tumors up to smallfingertip size were found in the submucosal layer. The cut surface of the tumors was yellowishwhite and well circumscribed. Histological pattern of the tumors was mainly type A mixed with a small area of type C of carcinoid. Fine argyrophilic granules were revealed in the cytoplasm by Grimelius staining. Many tumor cells showed positive reaction to antigastrin serum and scattered cells showed positive reaction to anti-VIP and anti-somatostatin sera by PAP method for immunoperoxidase staining. Electronmicroscopically, neurosecretory granules were found in the cytoplasm of many tumor cells.

　Tissue extracts from tumor were found containing 264,444pg of gastrin per gram in wet tissue. Serum gastrin level was restored to within normal range and the patient recovered very well after the operation.