Figure 1: (a)   T1-weighted, gadolinium-enhanced axial MRI showing the resection hole one day after surgical extirpation of a right frontal glioblastoma multiforme (1). Four months after surgery, fractionated radiotherapy (59 Gy), and chemotherapy with temozolomide, a new right periventricular tumor manifestation was observed invading the basal ganglia. An enhancement in the dorsal resection hole is evidenced, also indicating the local relapse (2). MRI gently provided by Professor A. Giese (Department of Neurosurgery, University of Mainz, Germany). (b) T1-weighted, gadolinium-enhanced axial MRI revealing a large left frontal glioblastoma. The illustration depicts the outer tumor border (as defined by the gadolinium enhancement) with glioblastoma cells migrating far away through the brain tissue.