Chemotherapy and novel therapeutic approaches in malignant gliomas

Glial neoplasms represent 0.5-1% of all cancers in most Western countries. Malignant gliomas are among the most devastating cancers, leading to death in most cases. They present unique challenges due to their location, aggressive biological behavior and diffuse infiltrative growth. Notwithstanding the development of new surgical and radiation techniques in the last thirty years, a cure for malignant gliomas remains elusive. In this article, we will review the standard and new therapies used for malignant gliomas. As standard therapies, surgery, radiation therapy and systemic chemotherapy, are in a continuous process of evolution. Multiple chemotherapies have been used in malignant gliomas, as single agents, in combination, or with different modes of administration, including high-dose chemotherapy with stem cell rescue and intra-arterial chemotherapy. The last decade has been noticeable for the advent of a better understanding of the biology of malignant gliomas. This has stimulated active research in multiples areas and the advent of new treatment strategies. Techniques to circumvent the resistance mechanisms to chemotherapy have been evaluated, tyrosine kinase inhibitors have shown activity in malignant primary brain tumors and radioimmunotherapy remains an area of active research. In this article, we review the past, present and future treatments of malignant gliomas with a special interest on chemotherapy, resistance mechanisms and tyrosine kinase inhibitors.