早期胃癌における内視鏡診断の進歩

Progress in the Diagnosis of Early Gastric Cancer

要旨　最近の約20年間の早期胃癌診断学の進歩を概観した．1962年の田坂らによる早期胃癌の定義・肉眼分類の発表は，それ以前の胃鏡，胃カメラ，胃X線検査などによる診断学の集大成であり，その後のファイバースコープ・二重造影時代への基盤をなすものとして，決定的な役割を果たしてきた．また，ファイバースコープ直視下胃生検法の確立は，早期胃癌の診断を，より確実・容易にし，生検法の普及を促進した．このような診断能の向上は，早期胃癌の発見数を増しただけでなく，早期胃癌の成長速度・成長様式（悪性サイクル，linitis plasticaなど）・発生母地などについての新しい知見をもたらした．近年では，一層の診断能の向上を目指して，色素内視鏡・拡大内視鏡・レーザー内視鏡・超音波内視鏡などが実用化されている．また，生検組織グループ分類の改正案を相い補うものとしても，新たな生検法strip biopsyが登揚したことの意義は大きい．結論としては，この20年あまりのわが国での早期胃癌診断の進歩は，十分な成果を収めたと言える．しかし，微小胃癌診断学の確立と発見率の向上，更には胃癌の予防までを目指して，今後より一層の努力が必要であろう．

　A survey on advancement in the diagnosis of early gastric cancer in the last 20 years was conducted. The definition and macroscopical classification of "Early Gastric Cancer" done by Tanaka et al in 1962 was accomplished through diagnostic methodology by means of gastroscope, gastrocamera, x-ray examination and others which were used before that time. It played a definitive role in forming the foundation for preparing the age of the fiberscope and doublecontrast method.

　Moreover, the establishment of gastric biopsy under direct viewing fiberscopy made the diagnosis of early gastric cancer more reliable and easier, promoting its wide use. By such developments in diagnostic capacity, the number of early gastric cancer detected increased and also, new findings about the growth rate, mode of development (for example, malignant cycle, linitis plastica. etc.) and the place of origin of early gastric cancer were obtained. Recently, dying endoscopy, magnifying endoscopy, laser endoscopy and ultrasonic endoscopy have been put into practice for improving the diagnostic capability. Moreover, a new method of gastric biopsy, "strip biopsy", has appeared to complement and serve as the revised edition of the group classification of gastric biopsy by Japanese Research Society for Gastric Cancer.

　Conclusively, the progress of the diagnosis of early gastric cancer in Japan in the last 20 years brought forth a substantial results. However, more effort is necessary to finaly establish the diagnosis of minute cancer, increase the ratio of discovery and also to prevent the gastric cancer.