[A multi-institutional study on postoperative adjuvant immunochemotherapy of gastric cancer (II)].

A multi-institutional cooperative study of postoperative immunochemotherapy for gastric cancer was studied using PSK and/or OK-432 combined with Tegafur (FT) and/or MMC. A total of 3,630 gastrectomized patients from 412 institutions were entered into the study using 6 randomly assigned protocols. Unbiased background cases were analyzed by 4-year or 5-year survival rates (SVR) for each protocol. The efficacy of combined PSK with FT was noticed in all cases of curative operation macroscopically and in n(-) X ps(+) cases (4-y SVR). The combination of MMC, FT and PSK produced better survival than MMC with FT or PSK administration in all cases of macroscopic curative operation (5-y SVR) and in non-curative operation (4-y SVR). The combination of MMC, FT, PSK and OK-432 was effective for poorly differentiated cancer (4-y SVR). Immunochemotherapy with MMC, FT, PSK and OK-432 was more effective in patients with preoperative positive PPD skin test than in those with negative PPD skin test. These results suggested that adjuvant immunochemotherapy using PSK and/or OK-432 combined with MMC and FT is effective for the improved survival of gastrectomized patients with gastric cancer.