1. Department for Oral and Cranio-Maxillo and Facial Plastic Surgery; University of Cologne; Cologne Germany
2. Center of Integrated Oncology (CIO); Cologne-Bonn Germany
3. Department for Oral and Cranio-Maxillo and Facial Plastic Surgery; Minden Germany
4. Department of Pathology; University of Cologne; Cologne Germany
5. Department of Oto-Rhino-Laryngology and Head Neck Surgery; University of Jena; Jena Germany
6. Department of Oto-Rhino-Laryngology and Head Neck Surgery; University of Cologne; Cologne Germany