非乳頭部十二指腸神経内分泌腫瘍（NEN）の鑑別診断—NET/NECのX線・内視鏡診断

Differential Diagnosis of Non-ampullary Duodenal Neuroendocrine Neoplasms（NENs）：X-ray and Endoscopic Diagnosis

要旨●非乳頭部十二指腸神経内分泌腫瘍（NEN）のX線造影所見・内視鏡所見を明らかにすることを目的として，当科において病理組織学的に非乳頭部十二指腸NENと診断した症例を対象に抽出し，遡及的にその臨床所見とX線造影所見・内視鏡所見を検討した．その結果，最近10年間に計14例15病変がNENと確定診断されており，NET 13例14病変（全病変G1）とNEC1例1病変に分類された．NET 14病変は全病変が十二指腸球部に位置し，内視鏡所見としては頂部にdelleを伴う黄白色調のSMT様隆起の形態が特徴的で，表面には白色観察およびNBI拡大観察で高率に血管拡張像と窩間部の開大を認めた．X線造影検査は7例に施行し，6例が透亮像として描出され，半数例でバリウム斑を伴っていた．切除標本を検討すると，13病変中2病変で病変表面に胃腺窩上皮化生を認めた．NECは下行部に位置し，IIa＋IIc様の形態を呈していた．

　This study aimed to elucidate the radiographic findings and endoscopic features of duodenal neuroendocrine neoplasms retrospectively diagnosed through pathological examination at our department. NEN was diagnosed in 15 lesions of 14 cases, NET G1 in 14 lesions of 13 cases, and NEC in one case. All 14 NET G1 cases were localized in the bulb. Endoscopic features were diagnosed as yellowish-white SMT-like elevation accompanied by a delle at the apex, and on the surface, white and NBI magnifying findings revealed a high rate of expanded blood vessels and enlargement of the interpapillary gaps. X-ray contrast imaging was conducted in seven cases, with six cases showing well-defined translucent images and three cases accompanied by barium spots. Examination of the resected specimens demonstrated gastric glandular epithelial metaplasia on the surface of two lesions of 13 cases. The NEC was located in the descending part and exhibited a IIa＋IIc-like morphology.