[Prevention of peritoneal recurrence by combined intra-peritoneal and intra-tumoral injections of OK-432].

Protective effect of OK-432 on peritoneal recurrence was examined in an experimental mouse model with Meth A fibrosarcoma injected into both abdominal wall and intraperitoneal cavity. OK-432 was given through either intratumoral (i.t.), intradermal (i.d.), intraperitoneal (i.p.), or i.p. + i.t. route. A significant antitumor effect against abdominal tumor was observed in mice given i.t. or i.p. + i.t. injection of OK-432. A significant protective effect against peritoneal recurrence and prolonged survival time was obtained in an i.p. + i.t. group, although other treatment groups showed only minimal effect. We conclude that combined i.p. and i.t. administration of OK-432 may prevent peritoneal recurrence and lead to prolongation in clinical patients with advanced GI tract cancer.