chapter  8
ByRoger E. McLendon, Allan H. Friedman, Linda Gray
Pages 28

Glioblastoma multiforme (GBM) is the most commonly occurring primary intracranial tumor in adults with an average incidence of 5 per 100 000 persons per year; however, an epidemiological nadir occurs from 17 to 20 years of age when the incidence of glioblastoma falls to 1 per million. These tumors are slightly more common in males than females and more common in Caucasians (Wrensch et al., 2002). The incidence of these tumors rises with increasing age (Cohen and Modan, 1968). The proposal that the incidence of primary malignant brain tumors is increasing seems to have been disproved by rigorous population controlled studies (Greig et al., 1990; Radhakrishnan et al., 1995). Glioblastomas can rarely be found in association with Li-Fraumeni syndrome or Turcot syndrome.