years. For patients that are over 30, the survival rate is lower but as treatment options grow, the survival rate is higher. However, a patient with bad general health is more likely to pass sooner than those that have good general health. Another study shows a 34% survival rate after 20 years. However, as discussed above, such figures can be misleading since they do not factor in the types of treatment nor the genetic signature of the tumors. Additionally, such historic data loses significance due to the relatively long survival of patients (compared to other types of brain tumors) and the introduction of newer treatment options over time. References External links Brain and Spinal Tumors: Hope Through Research (National Institute of Neurological Disorders and Stroke) CT and MR Scans Classic Radiology Imaging of Oligodendroglioma http://www.reseau-pola.org/app/download/24869531/La+Lettre_RENOP_5.pdf Brain tumor