早期胃癌臨床診断の実態―細胞診による早期胃癌診断の進歩

Development of Cytological Examinations for Diagnosis of Early Gastric Cancer

　胃内容より癌細胞を発見して癌の診断を下そうとする試みが19世紀後半より文献上に散見されるようになり，今世紀に入りPapanicolaou（1941年）による子宮癌の細胞学的診断法の大系づけにより，この方法が胃癌の診断に導入されて以来，細胞採取法にみられる幾多の変遷を経て現在に至っているのが胃細胞診の歴史である．この間，X線，内視鏡診断学の進歩と相俟って，早期胃癌の質的診断の面で，細胞診がとり上げられるようになって以来ほぼ10年になる．

　本稿では胃細胞診のこれらの歴史的な歩みを背景として早期胃癌診断において細胞診が果たした役割について述べたい．

　Author described the result of cytological examination for the diagnosis of early gastric cancer. Since 1955 to 1963, various cell collection method like as abrasive balloon method, x-chymotrypsin lavage, and endoscopical method by flexible gastroscope were applied for our clinic. During this period, since 1955 to 1961, 12 cases of early gastric cancer were examined by these technics, and the positive result was 70％. Also since 1962 to 1963, diagnostic result of early gastric cancer cases examined by these technics were 69.2％.

　Fibergastroscope for biopsy in 1964, and for lavage cytology under direct vision in 1965 were deviced in Japan. Since then, diagnostic result of early gastric cancer by cytological examination was increased remarkably. In this paper, cytology by fibergastroscope under direct vision means lavage cytology by fiberscope and direct smear cytology of biopsy specimen by fiberscope under direct vision. And 13 cases of early gastric cancer examined by these endoscopical methods of cytology were all positive.

　During these period, diagnostic results of early gastric cancer by various cell collection methods were as follows: by abrasive balloon method, 30 cases out of 42 were positive (positive rate was 72％), x-chymotrypsin lavage, 29 out of 39 were positive (74.2％ of positive) and cytology with flexible gastroscope, all of 3 cases were positive.

　Since 1967, new types of fibergastroscope using cool light source were used routinely in our clinic and since then up to date we examined 80 cases of early gastric cancer by lavage cytology, 81 cases by biopsy smear cytology and 119 cases by tissue biopsy method with fibergastroscope under direct vision. Positive results of lavage cytology was 85％, biopsy smear cytology was 86.4％ and tissue biopsy method was 83.2％. Among them, 13 cases of small early gastric cancer cases under 10 mm in diameter were examined by these technics. Positive result of lavage cytology with fibergastroscope was 50％, biopsy smear cytology was 58％ and tissue biopsy method was 62.5％. However for 5 cases of early cancer under 5 mm in diameter only one case was positive by biopsy smear cytology yand tissue biopsy method.

　Among these all cases, 8 were result of positive cytology and negative tissue biopsy examination.

　During these 17 years, various improvemnt of cell collection methods for cytological examinations were performed in Japan, and result of cytology with fibergastroscope is reliable for the diagnosis of early gastric cancer, and also using tissue biopsy method together with cytology showed almost 92％ of correct diagnosis of early gastric cancer cases