[Endoscopic administration of OK-432 in gastric cancer]

This paper describes the morphological and histological changes of gastric cancer following OK-432 injection into and around the lesion under endoscopic observation. Of 10 cases of unresectable gastric cancer, 7 revealed morphological changes and 3 a significant reduction of tumor size. In one of these cases, all the tumor cells disappeared. In 7 cases of resected gastric cancer preceded preoperatively by OK-432 administration, no obvious morphological changes were observed. However, histologically, marked infiltration of inflammatory cells was observed at the site of injection, especially in the submucosal layer. In regional lymph nodes, a lymphocyte predominance pattern which may have resulted from augmentation of T-cell activity was observed in many cases. The results suggested that local OK-432 injection therapy does not have such a marked direct effect on tumor cells, but may be useful as a means of prevention against invasion into the submucosal layer and regional lymph nodes.