転移性小腸腫瘍の画像診断・形態学的特徴

Diagnostic Imaging of Metastatic Small Intestinal Tumors（Morphological Features）

要旨●転移性小腸腫瘍は小腸腫瘍の中でもまれな疾患であるが，カプセル内視鏡検査やバルーン内視鏡検査といった小腸内視鏡検査が普及してきたことにより遭遇する機会が増加している．本稿では転移性小腸腫瘍を診断するのに有用な臨床的特徴を病態，検査，転移様式別（脈管性転移，直接浸潤，播種性転移）に，既報と自験例に基づいて概説した．転移性小腸腫瘍はさまざまな形態を呈するため，小腸腫瘍の鑑別疾患として念頭に置き，患者背景と検査所見から総合的に診断していく必要がある．

　Metastatic small intestinal tumors are rare among small intestinal tumors. However, they are increasingly encountered because of the popularity of enteroscopy such as capsule endoscopy and balloon-assisted endoscopy. In this article, we review the clinical features that are useful in the diagnosis of metastatic small intestinal tumors by pathogenesis, examination, and type of invasion（i.e., hematogenous/lymphogenous metastasis, direct invasion, and disseminated invasion）based on previous reports and our cases. As metastatic small intestinal tumors have various morphologies, they should be included in the differential diagnosis of small intestinal tumors and diagnosed comprehensively based on patient's background and laboratory findings.