Three main factors that sway the postoperative prognosis of stomach cancer are, the curability of the surgical operation, the depth of the cancer lesion and the stage of the disease. With these factors in mind, we further studied what other factors could influence the long-term prognosis of stomach cancer.
We picked up two categories of patients from our file of stomach cancer cases. Category one; those patients who survived five years or longer after surgery, although the operations for them were not curative, or the depth of the lesion in these patients reached to the serosa, or the cancer was in stage IV. Category two; those patients who died of stomach cancer within five years after surgery, although the operations were curative, or the depth of the lesion reached only the submucosal layer, or the cancer was in stage I.
By comparing these two groups, we found out the factors that influence the prognosis.
1) In the cases of absolutely curative operations, the factors that made the prognosis worse, were that the lesion was advanced, that the lesion existed in the C region, and that the lesion was poorly differentiated histologically.
2) In the cases of noncurative operations, caused by P1, H1, ow (+) or aw (+), factors that brought a good prognosis were, that the lesion was not of diffuse type, that there was no lymph node metastasis, and that lymph node dissection was done effectively.
3) In the cases of early gastric cancer, lymph node metastases made the prognosis worse. Even when the lesion reached the serosa, prognosis was favorable if cancer cells did not invade other organs, had no peritoneal dissemination, or if lymph node dissection was perfect.
4) In the cases of stage I histologically, prognosis was poor when the cancer looked advanced to the naked eye.
5) In the cases of stage IV, when the degrees of lymph node metastasis was slight and lymph node dissection was done adequate, prognosis was good.

We began gastric mass survey at our hospital in May, 1980. During 3 years and 8 months since then, (May, 1980-December, 1983) we performed screening examinations to 16, 341 people by indirect radiography, and checked 2, 824 cases (17.3%) for thorough examination. Among these cases, 2, 083 (73.8%) received endoscopic examination actually, and 55 cases of gastric cancer were discovered. The discovery rate of gastric cancer was 0.336 per cent.
35 cases of these 55 gastric cancer were operated in the surgical department of our hospital. 34 cases were resected (rate of resection was 97.1%) and 33 cases were resected curatively (rate of curative resection was 94.3%). These results were better than that of gastric cancer cases from out-patient clinic of the same period. The results of cases from out-patient clinic of our hospital were: total number of cases 321, resected cases 254 (79.1%), curative resection 189 cases (58.9%), respectively.