Treatment Strategies for Malignant Gliomas-2006(<SPECIAL ISSUE>Pathology and Treatment of Malignant Brain Tumors)

Abstract

In the treatment of glioblastoma (GBM), postoperative radiotherapy has been recognized as standard therapy, whereas the addition of chemotherapy has been a controversial issue. A meta-analysis based on 12 randomized trials suggested only a small benefit. The recent trial by the European Organisation for Research and Therapy of Cancer (EORTC) and National Cancer Institute of Canada Clinical Trial Group was the first study to demonstrate unequivocally that the addition of temozolomide to radiotherapy provides a statistically significant survival benefit in GBM. For anaplastic oligodendroglioma and oligoastrocytoma, two separate trials by EORTC and the Radiation Therapy Oncology Group clearly demonstrated that chemotherapy by procarbazine, lomustine, and vincristine, plus radiotherapy does not prolong survival but does increase the incidence of progression-free survival. The combined loss of 1p/19q identifies a favorable subgroup of oligodendroglial tumors, and no genetic subgroup could be identified that benefited with respect to survival from adjuvant PCV. In low-grade gliomas, older age, astrocytoma histology, presence of neurologic deficits, largest tumor diameter, and tumor crossing the midline were important prognostic factors for survival, and these factors can be used to identify low-risk and high-risk patients. Taken together, these evidences reported recently provide the most up-to-date treatment strategies for malignant gliomas.