This study will analyze tissue and blood samples from patients with gliomas (a type of brain tumor) to develop a new classification system for these tumors. Tumor classification can help guide treatment, in part by predicting how aggressive a tumor may be. Gliomas are currently classified according to their grade (how quickly they may grow) and the type of cells they are composed of. This system, however, is not always accurate, and sometimes two tumors that appear to be identical under the microscope will have very different growth patterns and responses to treatment. The new classification system is based on tumor genes and proteins, and may be used in the future to better predict a given tumor's behavior and response to therapy.

Patients with evidence of a primary brain tumor and patients with a known glioma who will be undergoing surgery to remove the tumor may participate in this study.

A sample of tumor tissue removed in the course of a participant's normal clinical care will be used in this study for laboratory analysis of genes and chromosome abnormalities. A small blood sample will also be collected for genetic analysis. In addition, clinical information on patients' condition and response to treatment will be collected every 6 months over several years. This information will include findings from physical and neurologic examinations, radiographic findings, and response to therapy, including surgery, radiation and chemotherapy.