1. Department of Oral and Maxillofacial Surgery, University Medical Center Groningen University of Groningen Groningen the Netherlands
2. Department of Pathology & Medical Biology, University Medical Center Groningen University of Groningen Groningen the Netherlands
3. Department of Otorhinolaryngology – Head & Neck Surgery, University Medical Center Groningen University of Groningen Groningen the Netherlands
4. Department of Epidemiology, University Medical Center Groningen University of Groningen Groningen the Netherlands
5. Department of Research Netherlands Comprehensive Cancer Organization (IKNL) Utrecht the Netherlands