内視鏡的に切除しえた十二指腸gangliocytic paragangliomaの1例

Gangliocytic Paraganglioma of the Duodenum Resected by Endoscopic Polypectomy, Report of a Case

要旨　患者は64歳，女性．検診の上部消化管造影検査にて十二指腸に隆起性病変を指摘．内視鏡検査にて十二指腸乳頭部のやや口側に山田Ⅲ型の径約2cmの表面平滑で軽度凹凸のある粘膜下腫瘍を認め，EUS（endoscopic ultrasonography）にて粘膜下層に低～高エコー輝度の混在する腫瘤を認めた．完全生検目的に内視鏡的切除を施行し，病理組織学的所見より，gangliocytic paragangliomaと診断した．本腫瘍は一般的に良性と考えられているが，本邦における報告例の大半は術前診断できずに膵頭十二指腸切除を含む外科的切除がなされている．したがって，術前診断が重要であり，内視鏡切除による完全生検は診断と治療を兼ねた方法と思われる．本症例は内視鏡的に切除しえた第3例目の症例である．

　A case of gangliocytic paraganglioma of the duodenum was reported. The patient was a 64-year-old woman. An upper gastrointestinal series of tests and endoscopy revealed a polypoid tumor in the second portion of the duodenum. Endoscopic ultrasonography showed the tumor with inhomogeneous echotexture in the submucosa. Endoscopic polypectomy was performed. Histopathologically, epithelioid cells were arranged in nests and ganglion-like cells were scattered and surrounded by spindle cells. Immunohistochemical staining for neuron specific enolase, S-100 and chromogranin showed positive results. Thus, the tumor was diagnosed as a gangliocytic paraganglioma. This disease is so rare that only 23 cases have been reported in Japan so far.