Abstract
OK-432, a Streptococcus hemoliticus preparation was administered into tumor and an area around the tumor in the stomach under the endoscopic observation, and clinical and pathological changes were studied. In 12 cases of resected gastric cancer in which this preparation was administered preoperatively, the granulation was noted at the site of administration and particularly characterized by a marked increase in histiocyte-like cells. In 25 cases of unresectable gastric cancer, endoscopic administration of OK-432 simultaneously with systemic immunochemotherapy was carried out and morphological changes were observed in eight cases. In one case out of them, tumor mass disappeared and cancerous tissue was no longer obtained by biopsy. In other seven cases, some inproved findings were found, such as flattening of elevated lesion, disappearance of ulceration and flattening of the base of ulceration. Biopsy was performed continuously in ten cases of unresectable cancer. In two out of them a pattern of degenerative changes in cancerous tissue along with a pattern of infiltration of inflammatory cells was observed. The 6-month survival rate was 55.1% and the 13-month survival rate was 27.2%. The survival rate of endoscopic injection group was significantly better than that of the group whose patients were treated only with systemic immunochemotherapy. The effect of in-flammatory cells, especially macrophage, are suggested as the significant role of the mechanism of OK-432 injected endoscopically.
