表層拡大型食道表在癌の内視鏡診断―臨床病理学的検討と内視鏡診断の精度

Endoscopic Diagnosis of Extensive Superficial Esophageal Cancer

要旨　食道癌取扱い規約の定義から，表層拡大型食道表在癌を0-Ⅱ型で表現される長径5cm以上の拡がりを示す表在型癌と解釈し，5cm未満の症例と臨床・病理学的特徴を比較検討した．表層拡大型食道表在癌は6例で，当科の表在型食道癌切除例の5.6％であった．全例全周性で深達度はm3 3例，sm2 3例，深達度の深い部分は病巣中央部で小範囲に複数の箇所でみられ，導管内伸展やリンパ管侵襲が多発する傾向が明らかとなった．術前の内視鏡診断の精度について，病理組織像と対比しながら検証した．病変内部のびらんや凹凸を細かく読み分けるためにはトルイジンブルー・ヨード二重染色法の併用が不可欠であるが，深達度の深い部位を正確に診断するのは難しく，実際の深達度よりも一段浅く診断する傾向がみられた．

　Clinico-pathological features of extensive superficial esophageal cancer which is defined as type 0-Ⅱ cancer more than 5 cm in diameter was studied in comparison with the same type of cancer less than 5 cm in diameter. Among superficial esophageal cancers resected in our department, there were six cases (5.6%) of extensive superficial esophageal cancer. The lesions in all six cases had whole-circle spread. Three of them were m3 cancer and the rest were sm2 cancer. The deeper part of invasion was found in several points in the small area near the center of the lesion. Ductal invasion and lymphatic permeation were positive multifocally. Reliability of pre-operative endoscopic diagnosis was studied in comparison with pathological findings. It is important to use toluidine blue and iodine double staining method for detection of slight erosive components or shallow elevation or depression on the surface of the lesion. However, it is difficult to make a precise diagnosis of the depth of invasion. There was a tendency to make a diagnosis underestimating the depth of invasion.