1. Department of Head and Neck Surgery, Poznan University of Medical Sciences, 61-866 Poznan, Poland
2. Department of Head and Neck Surgery, Greater Poland Cancer Centre, 61-866 Poznan, Poland
3. Department of Dermatology and Venereology, Poznan University of Medical Sciences, 60-355 Poznan, Poland
4. Radiotherapy Department II, Greater Poland Cancer Centre, 61-866 Poznan, Poland
5. Department of Electroradiology, Poznan University of Medical Sciences, 61-866 Poznan, Poland
6. Department of Dermatology, Poznan University of Medical Sciences, 60-355 Poznan, Poland