Cancer immunity and therapy using hyperthermia with immunotherapy, radiotherapy, chemotherapy, and surgery

Hyperthermia is a type of medical modality for cancer treatment using the biological effect of artificially induced heat. Even though the intrinsic effects of elevated body temperature in cancer tissues are poorly understood, increasing the temperature of the body has been recognized as a popular therapeutic method for tumorous lesions as well as infectious diseases since ancient times. Recently accumulated evidence has shown that hyperthermia amplifies immune responses in the body against cancer while decreasing the immune suppression and immune escape of cancer. It also shows that hyperthermia inhibits the repair of damaged cancer cells after chemotherapy or radiotherapy. These perceptions indicate that hyperthermia has potential for cancer therapy in conjunction with immunotherapy, chemotherapy, radiotherapy, and surgery. Paradoxically, the anticancer effect of hyperthermia alone has not yet been adequately exploited because deep heating techniques and devices to aggregate heat effects only in cancer tissues are difficult in practical terms. This review article focuses on the current understanding concerning cancer immunity and involvement of hyperthermia and the innate and adoptive immune system. The potential for combination therapy with hyperthermia and chemotherapy, radiotherapy, and surgery is also discussed