Postoperative immunochemotherapy including streptococcal lysate OK-432 is effective for patients with gastric cancer and serosal invasion.

The effects of postoperative immunochemotherapy including the streptococcal preparation OK-432 on the rate of peritoneal recurrence and survival time after curative resection were studied in 36 patients with gastric cancer. Patients randomized to group B received 18 months of a therapy that is widely used in Japan for patients with gastric cancer: mitomycin C (MMC) and UFT, a combination of tegafur and uracil in a molar ratio of 1:4. Patients randomized to group A received the same drugs given to group B plus an intraperitoneal injection of OK-432 on postoperative day 0 and intradermal injections of OK-432 for 18 months at 2-week intervals. There were no differences between the two groups in any known prognostic factor or dose of any drug received, except for OK-432. There was no difference in the toxicity rates between the groups. The concomitant administration OK-432 and anticancer drugs significantly decreased the rates of peritoneal recurrence and lengthened survival time (P < 0.05).