Life expectancy varies considerably based on the type of brain tumor and the patient's age, according to American Cancer Society. Sixty-five percent of people ages 20 to 44 with low-grade astrocytomas live five or more years, while five-year survival drops to 43 percent for 45- to 54-year-olds.
Low-grade astrocytoma patients ages 55 to 64 survive at least five years after diagnosis in 21 percent of cases, explains American Cancer Society. Some other relatively common forms of brain tumors are anaplastic astrocytomas, glioblastomas and meningiomas. Of these, meningiomas have the most favorable prognosis, with 92 percent of people ages 20 to 44 and 77 percent of 45- to 54-year-olds surviving for five or more years. The five-year survival rate is 67 percent for older adults ages 55 to 64 with meningiomas. Anaplastic astrocytomas have a less-favorable prognosis than low-grade astrocytomas, with five-year survival rates ranging from 49 percent to 10 percent.
Glioblastomas have one of the worst prognoses, as indicated by data from American Cancer Society. About 17 percent of patients diagnosed with glioblastomas between the ages of 20 and 44 live for five or more years. Those in the 45 to 54 age range survive at a rate of 6 percent following glioblastoma diagnosis, while only 4 percent of patients ages 55 to 64 live five years or more.