Glioma
This group comprises anaplastic astrocytomas and glioblastoma multiforme. Whereas the median overall survival of anaplastic (WHO grade III) gliomas is approximately 3 years, glioblastoma multiforme has a poor median overall survival of c. 15 months.
Survival rate
Sometimes the overall survival is reported as a death rate (%) without specifying the period the % applies to (possibly one year) or the period it is averaged over (possibly 5 years), eg. "Obinutuzumab: A Novel Anti-CD20 Monoclonal Antibody for Chronic Lymphocytic Leukemia".