消化管早期癌50年間の歩みと展望─病理診断学を中心に

The 50-year History and Prospects for Diagnostic Pathology of Early Gastrointestinal Carcinomas

要旨●雑誌「胃と腸」は，“日本の早期消化管癌の診断・治療・研究が，この50年間，世界のトップランナーであり続け，また，この成果を世界に届けながら異なった視点からの知識も導入して，今も進歩している姿”を伝えてきた．この分野では，特に，内視鏡診断学・治療学の進歩がすばらしく，世界の患者さんへ福音を日々届けている．このおかげで，この50年，日本の消化管病理診断学は飛躍的に進歩した．すなわち，HE染色を中心とした従来のHE診断病理学から免疫診断病理学，さらに今は治療の選択肢・患者予後も含めた治療・診断病理学へと変貌した．本稿では，50年の早期消化管癌の病理学的進歩の歴史から，以下のような代表的なものを選んで解説することにしたい．（1）消化器早期癌の定義の歴史，（2）消化管早期癌の肉眼型分類，（3）非浸潤性粘膜内癌（上皮内癌）と上皮内腫瘍（異形成）intraepithelial neoplasm（dysplasia）および日本と欧米での癌組織学的診断基準の違い，（4）分化型腺癌を細胞異型度から高低異型度に分けることの重要性．

　Japan has been a top runner in diagnosis, therapy and research of early gastrointestinal carcinoma of the world for the past 50 years, and still progressing with sharing the results and introducing（adopting）different foreign thinking ways. Especially, the endoscopic diagnosis and therapy have outstandingly advanced in giving the happiness to the patients of the world. With the endoscopic progression, the pathology on early gastrointestinal carcinomas also has been advancing in the past 50 years. That is, the pathology was in an early stage conventional histopathology mainly using hematoxylin-eosin stain, then immuno-histochemical pathology, and now has changed to diagnostic and therapeutic histopathology suggesting the choices on therapy and predicting patients' prognosis. In this article, I will make some general remarks upon representative results about early esophageal, gastric and colonic carcinomas in the past 50 years as follows;（1）Definition and its history,（2）Macroscopic classification and its changes,（3）Difference in definition of intramucosal non-invasive carcinoma（adenocarcinoma vs. dysplasia or intraepithelial neoplastic）between Japan and the West, and（4）Importance of cytologically dividing well-differentiated type adenocarcinomas into low- and high-grade atypia.