相対生存率曲線による早期胃癌の遠隔成績の検討および再発死亡例の分析

A Study on End Results of Gatsric Early Carcinoma: ana1ysis with relative survival rate carve

はじめに

　わが国において早期胃癌が注目されはじめてからすでに久しく，内視鏡の発達と普及により早期胃癌の発見には著しい成果がもたらされている．近年早期胃癌の5年生存例も数を増してきたが，早期胃癌の予後は絶対に良好であるという初期の報告に反して，早期胃癌再発例が報告されるようになった^{1)～8)12)14)}．第13回胃癌研究会においてもこの問題が取り上げられ，発表されたデーターの集計だけでも，早期胃癌1,700例弱のうち再発死亡例は70例余（約4％）におよんでいる．ここで東京大学第1外科の症例をもとに，早期胃癌再発の要因を分析しその対策を検討してみたい．

　By describing relative survival rate curve with life table method and life table, the authors have tried to obtain the standard error (+-2σ), availing themselves of 154 cases of early gastric cancer experienced in the years 1956 to 1967, including 15 recurrent cancer cases, with investigation of such items as sex, age, depth of invasion, endoscopic classification, size, histological type, lymph node metastasis, vascular invasion, CAT and SAT. The authors have also tried to ascertain main factors resposible for cancer recurrence by chi-square test of the above items among recurrent cases and all the early gastric cancer cases. Significant difference was found in the 7-year survival rate between positive vascular invasion and negative one; between ‘m’ and ‘sm’; 40 to 59 age brackets and over 60; between cancer 2 to 5 cm and that larger than 5cm in diameter. The depth of cancer invasion, lymph node metastasis and vascular invasion as factors for recurrence are no less important than stomal infiltration and multiple canoers in the gastric remnant. Liver metastasis accounts for most of recurrence pattern.

　Analysis of relative survival rate curve shows that prognosis of early gastric cancer must be estimated at a period 7 years or more after the initial surgical intervention. For cases of vascular invasion it is advisable to have recourse to more active management. It is also stressed that grouping of ‘sm’ cancer and that of ‘m' into the same category of early gastric cancer harbors some problems in the estimation of its prognosis.

　Based on these results, the authors have analyzed every recurrent case with reconsideration on the management of early gastric cancer and on the measures to guard against its recurrence.