食道小扁平上皮癌の拾い上げ診断―通常観察と生検診断

Diagnosis of Small Squamous Cell Carcinoma of the Esophagus by Conventional Endoscopic Examination and Chromoendoscopy with Iodine Staining

要旨　主に10mm以下のHGIN（high grade intraepithelial neoplasia）もしくは浸潤癌を食道小扁平上皮癌とした場合，通常内視鏡観察において重要な粘膜面の所見は，通常の早期食道癌と同様，かすかな発赤，細血管の乱れ，消失，わずかな凹凸，光沢の消失，白濁などであり，特に重要なのは発赤所見である．また，境界部分における細血管の途絶も重要な所見であり，小病変でも認識は困難ではない．さらに，やはりヨード染色を行うと発見は容易であり，ヨード不染帯が，HGIN以上かどうかの鑑別には，pink color signが有用である．小病変といえどもHGINは，浸潤癌となっていく可能性が高いと思われ，その発見に努力を注ぐべき対象であると考える．

　In this paper, we defined small squamous cell carcinoma of the esophagus as high grade intraepithelial sqamous neoplasia or invasive cancer with a diameter less than 1cm. The important mucosal findings of small squamous cell carcinoma of the esophagus are slight redness, disorder of the minute vessels, slight unevenness and slight whiteness. Especially, slight redness is the most important mucosal finding. The ability to detect small squamous neoplasia of the esophagus can be enhanced considerably by iodine staining during endoscopic examination. Small squamous cell carcinoma will be observed as an iodine unstained area, pink in color. Pink color sign is useful especially in patients with esophageal mucosa showing many minute iodine unstained areas. Because many high grade intraepithelial sqamous neoplasia lesions are considered to develop into invasive cancer, to find small or minute high grade intraepithelial sqamous neoplasia by precise endoscopic examination is clinically important.