1. Radboud University Medical Center Nijmegen, Nijmegen, Netherlands;
2. Radboud University Medical Center, Nijmegen, Netherlands;
3. Radboud University Medical Center, Department of Medical Oncology, Nijmegen, Netherlands;
4. Department of Oral and Maxillofacial Surgery, University Medical Center Utrecht, Utrecht, Netherlands;
5. VU University Medical Center, Amsterdam, Netherlands;
6. Erasmus University Medical Center, Rotterdam, Netherlands;
7. Antoni van Leeuwenhoek Hospital/Netherlands Cancer Institute, Amsterdam, Netherlands;
8. Leiden University Medical Center, Leiden, Netherlands;
9. University of Groningen, University Medical Center Groningen, Groningen, Netherlands;
10. Maastricht University Medical Center, Maastricht, Netherlands;
11. Department of Pathology, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands;
12. Department of Medical Oncology, University Medical Center Groningen, Groningen, Netherlands;