Glioblastoma multiforme (GBM) is diagnosed in approximately 3 out of every 100,000 people each year. Glioblastomas most frequently occur at advanced ages, and men are affected more often than women. Approximately 2,500 patients in Germany are diagnosed with glioblastoma every year.

Glioblastoma multiforme is one of the most common types of brain tumors that adults develop. It grows from glial cells known as astrocytes, the supporting tissue of the nervous system in the brain. The term glioblastoma comes from the histological structure, which resembles glial cells that occur naturally in the brain, while the term multiforme describes the heterogeneous appearance. Glioblastomas spread extensively and grow into other tissues, and they have a poor prognosis.

There is no obvious reason why individuals develop a glioblastoma. The distinction between primary and secondary glioblastoma specifies whether the tumor developed from healthy cells (“de novo” or completely new) or from cells that were already altered (e.g., from another tumor). It may occur in several members of the same family who are suffering from numerous, rare hereditary conditions.