1. INTRODUCTION
1.1 BACKGROUND ON GLIOBLASTOMA
1.1.1 EPIDEMIOLOGY
Cerebral tumors account for 1-2% of all cancers in Switzerland(1)(2). 58% of primary brain tumors are gliomas (1). Of the 500-700 (2) persons suffering from gliomas each year in Switzerland, 250- 300(3) have glioblastoma multiforme (GBM), which makes it the most common type of malignant primary brain tumor in adults, whereas cerebral metastases represent the majority of all brain tumors (4). Caucasian males living in industrial areas are believed to be most often affected by GBM (5)(6). Despite its controversial role in GBM pathogenesis, l'Office Fédéral de la Statistique (OFS) recommends limiting radiation from cell phone use (1).
1.1.2 CLINICAL MANIFESTATIONS
Clinical manifestations of GBM are variable - depending on the tumor's localization and rate of progression - and span a range of diverse signs and symptoms. However, the first manifestation of GBM is often a seizure, accompanied by a long-lasting atypical headache and a focal neurological deficit (7). General symptoms, such as nausea, vomiting, and loss of appetite, caused by increased intracranial pressure due to the tumor's mass surrounded by oedema are common (1). GBM rarely metastatizes, even though spreading through the subarachnoidal space to the spinal cord can occur (7). Its principal location is in the subcortical hemispheres, involving white matter (7) and, typically, fronto-temporal location is a predilection site (8). Clinical history is usually short, less than three months in 50% of patients affected by de novo GBM. However, secondary GBM, which accounts for 40% of cases (9) and arises from grade II or III gliomas, may have subtle manifestations for one-to-ten years before being diagnosed. It is often impossible to distinguish between a benign lesion and a malignant tumor based on the clinical history alone (10).