1. Department of Otolaryngology Head and Neck Surgery, Helios Amper-Klinikum Dachau, Dachau, Germany
2. Department of Otolaryngology Head and Neck Surgery, Technical University of Munich, Munich, Germany
3. Medizinische Klinik und Poliklinik I, University of Munich, Munich, Germany
4. Institute of Pathology, University of Düsseldorf, Düsseldorf, Germany
5. Department of Otolaryngology Head and Neck Surgery, Section of Phoniatrics and Pedaudiology, University of Ulm, Ulm, Germany
6. University Medical Center Regensburg, Department of Gynecology and Obstetrics, Regensburg, Germany