大腸内視鏡検査で発見された終末回腸の微小癌・腺腫の1例

Diminutive Adenoma and Intramucosal Carcinoma of the Terminal Ileum Found in Routine Colonoscopy, Report of a Case

要旨　患者は83歳，男性．下痢・肛門部痛を主訴として当科を受診．大腸内視鏡検査を施行したところ，回盲弁より約3cm口側の終末回腸に境界明瞭で頂部にわずかなくぼみを有する約5mm大の軽度発赤調扁平隆起を，更にこの約1cm口側に同様の形態を呈する約2mm大の扁平隆起を認めた．両病変に対して内視鏡的粘膜切除術を施行した．実体顕微鏡で固定標本を観察したところ，両者とも病変表面の絨毛構造は消失し，陰窩開口部は大腸腺腫に類似した小管状～樹枝状模様を呈していた．各々の病理診断は腺腫併存粘膜内管状腺癌(高異型度)および腺管腺腫であった．

　An 83-year-old man was referred to colonoscopy because of diarrhea and anal pain. The colonoscopic examination revealed two diminutive polyps of the terminal ileum, located at about 3 to 4 cm on the proximal side from the ileocecal valve. One was a brownish tumor, about 5 mm in size, with a narrow hollow in the center of the surface, and the other, about 2 mm in size, had the same appearance as the former. Endoscopic mucosal resection was performed, and histological examination revealed well differentiated adenocarcinoma (high grade) with adenoma, and tubular adenoma, respectively. The dissecting microscopic examination of the surface structure of both tumors showed small tubular and gyrus-like pits, similar to those of colorectal adenomas, without normal villi.