TTFields General Routine Clinical Care in ndGBM Patients: a French Prospective Non-Interventional Study (TIGER France)

Inclusion Criteria:

* Participant aged ≥ 18 years old.
* Participant with newly diagnosed GBM.
* Participant who completed radiochemotherapy after surgery or biopsy.
* Participant within first 2 cycles of maintenance TMZ.
* Participant for whom the physician has decided to initiate treatment with Optune® according to Instruction For Use or medical guidelines.

Exclusion Criteria:

* Participant currently participating in a prospective clinical trial studying a different treatment than the one studied in this current prospective study.
* Patient currently breastfeeding.
* Patient who is pregnant, thinks she might be pregnant or is trying to become pregnant. Patient of childbearing potential must use a contraceptive method for the whole duration of their participation in the study.
* Patient suffering from a significant neurological disease (primary epilepsy, dementia, progressive degenerative neurological disorder, meningitis or encephalitis, hydrocephalus associated with increased intracranial pressure).
* Patient with a known sensitivity to conductive hydrogels, such as gel used with electrocardiogram (ECG) or transcutaneous electrical nerve stimulation (TENS) electrodes.
* Patient with an active implanted medical device, a cranial defect (such as a missing bone that has not been replaced) or bullet fragments. Active electronic devices include, for example, deep brain stimulators, spinal cord stimulators, vagus nerve stimulators, pacemakers and defibrillators.
* Participant being deprived of liberty by a judicial or administrative decision, or who is under a measure of legal protection (e.g. guardianship or curatorship).