集検発見胃癌の時代的変貌

Transfiguration of Gastric Cancer Detected by Mass Survey

要旨　集検対象の拡大と高齢化，一次検診と精検に用いる機器・技術の進歩に伴い，集検発見胃癌は過去25年間に変化を来している．当施設で治療を行った集検発見胃癌でみた場合，早期癌比率が一貫して増加しており，最近では72.5％に達した．早期癌肉眼型では混合型が減少し，陥凹型が増加傾向にある．進行癌肉眼型ではBorrmann 2型が増加し，3型，4型が減少している．癌巣が小さく深達度の浅い例が増加し，癌巣が大きく深達度の深い例が減少している．組織型ではpapとtub₁が増加し，sigが減少している．陥凹型早期癌の癌巣内潰瘍保有率は最近になって減少してきた．集検発見胃癌の生存率は向上し続けており，近年の5年粗生存率83.7％を得ることができた．

　554 cases of gastric cancer detected by mass survey were treated in our hospital during the period from 1967 to 1991. Among the transfigurations in these cases, the most prominent feature was the increased rate of early gastric cancer. Its current rate is 72.5% of all the gastric cancers detected by mass survey. In macroscopic types of early gastric cancer, mixed types showed a decrease in frequency and depressed type cancers showed an increase in frequency. In regard to macroscopic classification of advanced gastric cancer, Borrmann 2 has increased and Borrmann 3 and 4 have decreased. The size of lesions have become smaller and the depth of lesions has become shallower. In histological classification, papillary adenocarcinoma and welldifferentiated tubular adenocarcinoma increased in frequency and signet-ring cell carcinoma decreased. The frequency of peptic ulcers within cancerous lesions has decreased recently. A five-year survival rate of gastric carcinoma patients detected by mass survey has increased gradually to 83.7% of all cases during 1984-1986. It is concluded that mass survey of gastric cancer has detected cancers as early as possible and has increased survival rates.