Development of immunotherapy for the treatment of malignancies refractory to conventional therapies.

The key to understanding cancer has eluded scientists for years. As we discover new and more effective approaches to the treatment of cancer, the more we have yet to explore. Despite landmark advances in molecular biology and surgical adjuvant therapy in the past decade, cancer remains a significant life threat. Most metastatic cancers are refractory to conventional therapies, including surgery, radiation therapy and chemotherapy. Therefore constant efforts are being made to develop more effective treatment modalities. Immunotherapy, which is based on the enhancement of an immune response against the host tumor, has been particularly promising. In this review, we shall address the origins, development and future directions of immunotherapy.