[Changes in nonspecific suppressor factors in the serum of gastric cancer patients after surgery and immunochemotherapy].

After curative surgery for gastric cancers judged macroscopically to be at stage 2 or 3, patients were divided into 4 groups by randomization. As the basic treatment, patients were given one-shot Mitomycin and Tegafur as maintenance therapy for 8 months (group A). PSK (group B), OK-432 (group C) or both PSK and OK-432 (group D) were added to the treatment of group A for 8 months. Sera were obtained from these groups of patients at 4 weeks and 3, 6, 9 and 12 months after surgery. In all of these groups, values of IAP increased slightly at 4 weeks but decreased at 3 months and were maintained at such a level by 12 months. On the other hand, suppressive effects of such sera on the blastogenesis of murine spleen cells in response to PHA varied among these group. In groups A and C, the suppressive effect of sera increased after surgery and was detected continuously by 12 months. In groups B and D, in contrast, the suppressive effect disappeared from 3 to 12 months. The rise and fall of such a suppressive effect of sera may reflect the mode of action of PSK.