This study will combine MR imaging techniques together with elaborate neuropsychological assessments and RT dosimetry in 120 patients who will be examined baseline (before RT) and followed longitudinally after RT.~The first objective is to build an NTCP model for neurocognitive decline after RT (for each cognitive domain separately), linking dose-volume parameters to structures within the brain susceptible to neurological damage and neurocognitive decline after radiotherapy. These NTCP models can be used to make predictions on neurocognitive decline in future primary brain tumour patients receiving cranial RT.~The second objective is to evaluate dose-dependent neurocognitive decline. In particular, the investigators will assess:~Prevalence and severity of neurocognitive decline after RT for all cognitive domains~Brain structures or functional brain connections important in neurocognitive functioning (based on dedicated MRI).~Dose-dependencies of specific neurocognitive skills after RT in adult brain tumour patients~Correlations between RT dosimetry and early brain changes (MRI)
The goal of this multicenter prospective longitudinal study is to study the long-term impact of multimodal treatment (chemotherapy, radiotherapy and surgery) in adult brain and base of skull tumors on neurocognitive functioning.~All included patients will complete a self-report inventory (subjective cognitive functioning, QoL, confounders), a cognitive test battery, an advanced MR at multiple timepoints. Moreover, toxicity will be scored according to the CTCAEv5.0 in these patients over time.