生検により変性した粘液が“naked fat sign”様に流出した粘膜下異所性胃腺の1例

Submucosal Ectopic Gastric Gland with Denatured Mucus Resembling a “Naked Fat Sign” from the Mucosal Defect Identified by Biopsy, Report of a Case

要旨●粘膜下異所性胃腺の多くは開口部の特徴的形態から画像的に診断が可能であるが，生検では証明されないこともある．筆者らは二こぶ隆起の粘膜下隆起を呈する粘膜下異所性胃腺を経験した．一方の隆起部上には開口部がみられ，画像的には粘膜下異所性胃腺を疑ったものの，開口部からは生検では間質系細胞のみしか得られなかった．もう一方の隆起部の生検では，軟らかい固形物が脂肪腫でみられるnaked fat sign様に出てきた．確定診断がつかずESDにて一連の胃粘膜下異所性胃腺と診断した．生検で得られた検体は病変内の肉芽組織で，軟らかい固形物は変性した粘液と考えられた．

　The diagnosis of many submucosal ectopic gastric glands can be established through endoscopic imaging based on the characteristic morphology of the orifice ; however, this may not be histologically proven. We encountered a case of a submucosal ectopic gastric gland with a double-humped subepithelial lesion. Although we suspected a submucosal ectopic gastric gland based on the imaging of the characteristic orifice, the biopsy sample obtained from the orifice of one protrusion revealed mesenchymal cells only. A soft, solid matter resembling a “naked fat sign” appeared from the mucosal defect identified by biopsy on the other protrusion. The soft solid matter was considered denatured mucus.