胃と腸51巻5号

2016年05月発行

増刊号 消化管拡大内視鏡診断2016 主題研究

拡大内視鏡により視覚化される白色不透明物質

著者： 八尾建史¹ 上尾哲也² 遠城寺宗近³ 久部高司⁴ 今村健太郎¹ 松永和久⁵ 植木敏晴⁴ 田邉寛⁶ 岩下明德⁶

所属機関： ¹福岡大学筑紫病院内視鏡部 ²大分赤十字病院消化器内科 ³福岡大学薬学部臨床薬物治療学 ⁴福岡大学筑紫病院消化器内科 ⁵福岡大学薬学部創剤学 ⁶福岡大学筑紫病院病理部

ページ範囲：P.711 - P.726

要旨●消化管粘膜の胃腸上皮化生，胃上皮性腫瘍，大腸上皮性腫瘍において，拡大内視鏡検査により視覚化される白色不透明物質（WOS）の臨床的意義や病態に関する文献をレビューし，報告する．その臨床的意義は，WOSの存在や形態学的特徴による癌・非癌の鑑別診断，胃上皮性腫瘍の粘液形質の推定，WOSを応用した脂肪負荷試験の開発などである．WOSの正体は，上皮内，上皮下に集積した微小な脂肪滴である．集積した微小な脂肪滴に光を投射すると，脂肪滴により強く後方散乱または反射した光が，ヒトの知覚で白色として捉えられ，上皮下の微小血管まで投射光が到達しないため，血管が視覚化されない現象を生じる．脂肪滴の由来は不明であるが，胃上皮性腫瘍に脂肪滴が集積する病態については，腫瘍細胞では，脂質を蓄積（脂肪産生，脂肪滴生成）する遺伝子群に比べて，消費（β酸化，分泌，脂肪分解）する遺伝子群の発現が抑制されるため，脂質が蓄積していることが判明した．WOSは，食道腺癌，十二指腸上皮性腫瘍にも認められ，全消化管に存在しうることが明らかとなった．WOSは，全消化管粘膜について内視鏡診断や病態解明に有用な新しいマーカーとなりうることが示唆された．

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