Immunotherapeutic agents have become important additions to the list of anti-cancer treatments; further progress will require more information about how the immune system can respond to tumor cells. Tumor cells can avoid eliciting an immune response through several mechanisms. Understanding these mechanisms may suggest strategies to manipulate tumor cells so that they trigger an effective immune response. Another strategy being developed is to improve the therapeutic index of cytokines so that better anti-tumor effects can be elicited with less toxicity.
