The most common primary brain tumors in adults are called gliomas. These are cancers that originate from the glial cells that hold the brain together (glial means glue in Greek). A recent update on understanding and treating glioblastoma is here. The current treatment approach is combining new molecularly targeted drugs with radiation as noted here. Vaccine trials (immunotherapy) are also showing promise go here. For instance one trial with dendritic cell vaccines pushed the median survival from 15 months to 26 months and another vaccine trial improved the 3 year survival from 3% to 37%.
Start with a review of brain anatomy and imaging and then read the best sites about understanding these tumors. Then read the section on treatment of check out the NCCN guidelines. There is a section on survival and outcome statistics and a section on all other topics.
Other types of brain tumor, low grade gliomas and brain metastases are noted elsewhere.