1. Sahlgrenska Cancer Center, Department of Pathology and Genetics, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
2. Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
3. Department of Clinical Pathology and Cytology, Sahlgrenska University Hospital, Gothenburg, Sweden
4. Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
5. Department of Neurosurgery, Sahlgrenska University Hospital, Gothenburg, Sweden
6. Department of Neurosurgery, St Olavs University Hospital, Trondheim, Norway