Barrett食道癌の病理学的特徴―接合部腺癌，噴門部胃腺癌との対比

Pathologic Analysis of the Adenocarcinoma of the Lower Esophagus and Esophagogastric Junction, including Barrett's Adenocarcinoma and Non-Barrett's Adenocarcinoma

要旨　粘膜下層までにとどまる下部食道・食道胃接合部領域の腺癌26例を病理学的に検討した．食道腺癌，接合部腺癌，噴門部胃腺癌間で組織像に明瞭な差異は認められないが，Barrett食道長が長いものには，粘膜内低分化腺癌成分を含む病変，0-IIb成分，腫瘍・非腫瘍の鑑別が困難な異型腺管の出現がやや多い傾向にあった．下部食道・食道胃接合部領域に発生する腺癌は，大部分がGERDを背景に発生するという共通点があり，病理学的特徴にも類似性があるが，Barrett食道の長さを規定する因子によって，異なった群に分けられる可能性がある．特にBarrett食道長の短いものやBarrett食道を伴わないものに関しては，Barrett粘膜を介さない直接的発癌が本態で，Barrett食道は傍癌的な位置づけである可能性がある．

　Totally 26 cases of adenocarcinoma of the lower esophagus and EGJ（esophagogastric junction）, limited to the mucosa or submucosa, were examined. There were no significant differences in pathologic characteristics among three groups of esophageal adenocarcinoma, adenocarcinoma of the esophagogastric junction, and adenocarcinoma of the proximal stomach. However, the existences of a poorly differentiated component, 0-IIb component, and atypical glands with indefinite for neoplasia were relatively frequent in the lesions with greater length in the Barrett's esophagus. Although adenocarcinomas of the lower esophagus and esophagogastric junction have been found under the common condition of gastroesophageal reflux disease, they may be divided into two groups such as adenocarcinoma with and without preceding Barrett's mucosa. For the latter group, Barrett's esophagus may be a paracancerous condition rather than a precancerous lesion.