1. Amsterdam University Medical Center, University of Amsterdam, Cancer Center Amsterdam, Amsterdam Gastroenterology Endocrinology Metabolism, Laboratory Genetic Metabolic Diseases, Amsterdam, the Netherlands
2. Medisch Spectrum Twente, Department of Oncology, Enschede, the Netherlands
3. Department of Clinical Chemistry and Laboratory Medicine, Medisch Spectrum Twente, Medlon BV, Enschede, the Netherlands
4. Department of Neurology, Medisch Spectrum Twente, Enschede, the Netherlands
5. Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
6. Department of Clinical Pharmacy and Pharmacology, University Medical Centre Groningen, University of Groningen, Groningen, the Netherlands
7. Martini Hospital Groningen, Certe Department of Clinical Chemistry, the Netherlands
8. Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
9. Department of Chemistry, Uppsala University, Biomedical Center, Uppsala, Sweden
10. MRC-Holland bv, Amsterdam, the Netherlands
11. Departments of Clinical Pharmacy and Medical Oncology, Isala, Zwolle, the Netherlands