ABSTRACT
In the United States alone, more than 17 000 new cases of primary malignant brain tumor are diagnosed per year, and the incidence appears to be increasing.
Studies using data from the Surveillance, Epidemiology, and End Results (SEER) registry report that the incidence of primary tumors of the CNS is between 2 and 19 per 100 000 per year depending on age.1 From birth to age 4 years the incidence of primary brain tumors is approximately 3.1 per 100 000, and then slowly declines to a nadir of 1.8 per 100 000 in persons aged 15-24 years. The incidence then rises again to a relative plateau at around age 65 years, with an incidence of approximately 18 cases per 100 000 persons. The most common and serious malignant neoplasm is glioblastoma multiforme (GBM), which accounts for 23% of cases, and is among the most lethal and difficultto-treat cancers: median survival is less than 1 year from the time of diagnosis.2
