微小胃癌の内視鏡診断の現状と今後の方向づけ

Present Status of Endoscopic Diagnosis of Minute Gastric Cancer and Its Future

　内視鏡の進歩は，胃内観察ではすでにミクロの世界に突入しようとしている．胃癌の早期診断を唱える立場とすれば，大変夢のある喜ばしいことであるが，胃癌診断の現実は微小胃癌が10mmか5mmかで議論されている段階である．さらに昨年（1978年）秋の第20回日本消化器病学会秋季大会シンポジウムで示されたように，胃癌の発生頻度からみれば，10mm以下としても微小胃癌の症例はあまりにも少ない．このような事態の原因はどこにあるのであろうか．

　早期胃癌分類が生まれて15年を過ぎた．この間，胃生検をはじめ，内視鏡機器の開発，改良は目ざましいものがある．しかし，これを使用し，診断する内視鏡医の心構えはどうであろうか．内視鏡の大家といわれる人々の診断法を慢然と踏襲していたのではなかろうか．胃生検に甘えているのではなかろうか．

　To make an accurate diagnosis of minute gastric cancer, it should be realized that routine endoscopic observation and picture-taking are inadequate and we have to do extensive endoscopic observation and appropriate picture-taking in every nook and corner of the stomach. In another words, conventional endoscopic method, which is mainly consist of picturetaking, is inadequate for diagnosing minute gastric cancer and it is important to do extensive endoscopic observation first, then picture-taking from the suspicious lesions. Establishing new endoscopic method as well as improving the endoscopic instrument to meet above standards are the key factors for accurate diagnosis of minute gastric cancer.

　Analyzing 44 lesions of minute gastric cancer, in which 7 lesions were less than 5mm in diameter and the rest of them were less than 10 mm in diameter, we discussed present status of endoscopic diagnosis of minute gastric cancer and its future problems.

　Endoscopically,14 out of 44 lesions were diagnosed as gastric cancer and 16 lesions were felt to be possible gastric cancer. However,5 lesions were misdiagnosed as benign lesion and further more 9 lesions were overlooked. The cause of these misdiagnosis and overlooking is mainly due to inadequate approach to the minutegastric cancer, namely inadequate endoscopic observation and picture-taking.