Endoscopic intratumoral injection of ok-432 and langerhans' cells in patients with gastric carcinoma

Abstract
OK-432, a compound composed of penicillin G-treated, attenuated streptococcus pyogens of human origin, was administered by intratumoral injection (IT) to 15 of 49 patients with Stage III gastric carcinoma, at the time of preoperative endoscopic examination. The 5-year survival rate of patients given IT was 73.3%, whereas the rate was only 36.5% in those not given IT (P> 0.05). A study of recurrent cases revealed a significantly low incidence of peritoneal recurrence in the group on OK-432 IT (P > 0.01). In previous work, the authors noted a favorable prognosis of patients with Stage III gastric carcinoma and with a marked infiltration of Langerhans' cells (LC) in the tumor tissues. All of the 49 in the current study were thus examined immunohistochemically, using anti-S-100 protein antibody, the objective being to clarify the relationship between OK-432 IT and the density of LC. The density of LC among those given IT was significantly increased as compared with those not given IT (P > 0.05). The results of this study suggest that OK-432 IT may lead to augmentation of the density of LC in tumor tissues and hence prevent peritoneal recurrences in patients with Stage III gastric carcinoma.