PURPOSE: We analyzed the effect of intraperitoneal immunotherapy in an animal model mimicking locoregional dissemination of tumor cells during resection of advanced tumors. METHODS: We first established a tumor model with human gastric cancer cells (MKN-45) in the peritoneal cavity of CB-17-SCID mice. Three hours following the injection of tumor cells into the peritoneal cavity, mAb 17-1A alone and in combination with human LAK cells were given intraperitoneally at different dosages. The results were quantified by determining the weight of the peritoneal tumor masses. RESULTS: After intraperitoneal administration of 17-1A mAb, a tumor reduction could be shown (median tumor mass after 10 microg mAb: 171 microg; after 100 microg: 130 microg) when compared with the control group (632 microg). Following a combined therapy with mAb and LAK cells, a statistically significant tumor reduction could be observed (after 10 microg mAb + 20-50 x 10(6) LAK cells: 80 microg; after 100 microg mAb + 20-50 x 10(6) LAK cells: 12 microg, p = 0.0005). With specific dosages of antibody and LAK cells it was even possible to achieve complete tumor clearance. CONCLUSIONS: Intraperitoneal immunotherapy reduces the peritoneal tumor masses and can even prevent the peritoneal carcinomatosis formation. Copyright 2003 S. Karger AG, Basel
PURPOSE: We analyzed the effect of intraperitoneal immunotherapy in an animal model mimicking locoregional dissemination of tumor cells during resection of advanced tumors. METHODS: We first established a tumor model with humangastric cancer cells (MKN-45) in the peritoneal cavity of CB-17-SCIDmice. Three hours following the injection of tumor cells into the peritoneal cavity, mAb 17-1A alone and in combination with humanLAK cells were given intraperitoneally at different dosages. The results were quantified by determining the weight of the peritoneal tumor masses. RESULTS: After intraperitoneal administration of 17-1A mAb, a tumor reduction could be shown (median tumor mass after 10 microg mAb: 171 microg; after 100 microg: 130 microg) when compared with the control group (632 microg). Following a combined therapy with mAb and LAK cells, a statistically significant tumor reduction could be observed (after 10 microg mAb + 20-50 x 10(6) LAK cells: 80 microg; after 100 microg mAb + 20-50 x 10(6) LAK cells: 12 microg, p = 0.0005). With specific dosages of antibody and LAK cells it was even possible to achieve complete tumor clearance. CONCLUSIONS: Intraperitoneal immunotherapy reduces the peritoneal tumor masses and can even prevent the peritoneal carcinomatosis formation. Copyright 2003 S. Karger AG, Basel