早期胃癌の予後

Prognosis of Early Gastric Cancer

要旨　早期胃癌の予後に関して局所切除34例を含めた外科切除例1,486例を解析した．死亡例の死因に占める原病死の割合は25％と低率であり，最も多い死因は他臓器の癌であった．この2次癌の発生の問題は今後ますます大きくなると思われる．また，5年以降の再発死亡が全再発死亡中の30％に達することから，早期胃癌においては5年以降もフォローアップが大切であること，予後の評価は5年生存率だけでは不十分であることがわかった．全体の予後では5年生存率，10年生存率各92.2％，85.3％と良好で，sm癌では89.7％，81.2％であったが，他病死を除外すると，sm癌でも96.7％，91.9％と癌の中では極めて予後の良い癌であると言える．

　To evaluate the prognosis of early gastric cancer, we analyzed 1,486 patients treated surgically in the National Cancer Center Hospital (Tokyo) during the period between 1975 and 1989. Only 25% of 146 post-operative deaths were due to recurrence of gastric cancer. The most common cause of post-operative deaths was malignant disease arising from other organs (48 cases). The more often the early diagnosis of primary cancer is made, the more clinically important this secondary cancer will be. Thirty percent of deaths due to recurrence occurred over five years after surgery. A five-year period is regarded as a standard observation period for cure rate of gastric cancer. This result suggests that careful follow-up should be continued even after five years of observation, and that mortality of gastric cancer should be evaluated by both five-and ten-year survival rates. The actual survival rates of gastric cancer were excellent; 92.2% at five years and 85.3% at ten years after surgery.Although the survival rates of tumors invading the submucosal layer were not as good as those of mucosal cancer, they were 89.1% at five years and 81.2% at 10 years. Their survival rates excluding non-cancerous deaths were quite good, 96.7% at five years, and 91.9% at teny ears. The five-year survival rate of submucosal cancer with lymph node metastasis was 89.8% when non-cancerous deaths were excluded.