腹膜播種に対するBCG. Levamisole免疫療法

BCG and levamisole (LMS) immunotherapies were applied to an experimental model of cancer in the digestive organs by considering the abdominal wall as the intestinal tract wall. Ehrlich ascites tumor cells transplanted subcutaneously into the abdominal wall of mice invaded to the parietal peritoneum in approximately two weeks. Afterwards the tumor cells appeared in the peritoneal cavity, following retention of ascites. Almost all tumor bearing mice died within three weeks after the appearance of tumor cells in the peritoneal cavity. Presensitized BCG showed significant suppressive effects on tumor growth compared with the control in tumor diameter and mean survival, but in the groups administered BCG after tumor transplantation and those administered BCG before and after tumor transplantation, there were no significant regressive effects. In two groups of mice administered BCG before tumor transplantation, the appearance of tumor cells in the peritoneal cavity was delayed. LMS administrated 3 days before tumor transplantation did not show any effects. In two groups administered LMS after tumor transplantation, LMS showed some effects, but with no significant difference in any parameters. In the group administered LMS 14 days after tumor transplantation, the appearance of tumor cells in the peritoneal cavity was delayed. BCG was probably superior to LMS administered before tumor transplantation, though the timing of the administration was questionable. LMS seemed to be effective even 14 days after tumor transplantation.