1. Department of Medical Oncology; Erasmus University Medical Center/Daniel Den Hoed Cancer Center; Groene Hilledijk 301 3075 EA Rotterdam The Netherlands
2. Department of Neurology; Erasmus University Medical Center; Rotterdam's-Gravendijkwal 230 3015 CE Rotterdam The Netherlands
3. Department of Medical Statistics; Erasmus University Medical Center/Daniel Den Hoed Cancer Center; Groene Hilledijk 301 3075 EA Rotterdam The Netherlands