回腸カルチノイドの1例

Carcinoid Tumor of the Ileum, Report of a Case

要旨　患者68歳，女性．1981年ごろより2年間以上にわたり，体重減少と消化管閉塞症状を繰り返す．小腸X線検査にて狭窄病変を認め手術を行った．回腸端より口側120cmに大きさ4cmのカルチノイド腫瘍を認めた．Douglas窩に転移を疑う腫瘤を触知したが，リンパ節，肝には転移はみられなかった．組織学的には典型的なカルチノイド腫瘍で，漿膜浸潤を来していた．一般的な組織化学染色で銀親和性は陽性，免疫染色でセロトニンが陽性であった．Douglas窩転移巣によると思われる疼痛が術後2年以上続き，他因死した．血中セロトニン，一日尿中5-HTT(5 hydroxyindole acetic acid)は全経過中基準値範囲内であった(術後)．本症の4cm以下の病変の存在診断は小腸内視鏡や逆行性小腸造影検査が有効と考えられる．

　A 68-year-old female had been suffering from repeated symptoms of small bowel obstruction and consequent weigth loss, for more than 3 years since 1981.

　Rediologic examination of the small bowel was able to detect a spherical lesion in the distal ileum. It was resected surgically. No metastasis was found in the liver and regional lymph nodes, but dissemination was suspected in the culdesac.

　Histopathologically, the lesion was diagnosed as a classical carcinoid tumor (sized 4 cm). It invaded to the serosa, lymphatics and submucosal nerves. Histochemically, it was argentaffin (Fontana-Masson staining) and, immunohistochemically, serotonine was found in the tumor cells. Serum serotonine level was normal and the quantity of 5 hydroxy indole acetic acid daily excreted in the urine was also normal.

　The patient suffered from severe pain in the perineal region and lower abdomen for more than 2 years post-operatively. Recurrence was highly suspected, but the patient suicided. Throughout the whole course of our examination, no carcinoid syndrome had appeared. We suggest that endoscopy for the small bowel and retrograde small bowel enema by using colonoscopy are effective to detect small carcinoid tumors (less than 1 cm).