Discrepant effects of interferon murine syngeneic ascites tumors and their solid metastasizing counterparts

The effects of interferon on mice with syngeneic tumors growing either intraperitoneally or as solid tumors were analyzed. The same dose that depressed the growth of ascites tumors, enhanced growth and in one case metastasizability of the corresponding solid tumors. The possibility that this was due to some host reaction is discussed. It seems important to develop animal models for analyzing interferon effects before treatment is initiated in human tumor disease.