[1] GSF Forschungszentrum Umwelt & Gesundheit GMBH, Inst Pathol, D-85764 Neuherberg, Germany
[2] GSF Forschungszentrum Umwelt & Gesundheit GMBH, Inst Biomath & Biometry, D-85764 Neuherberg, Germany
[3] Univ Ulm Klinikum, Dept Otolaryngol Head & Neck Surg, Ulm, Germany
[4] Tech Univ Munich, Dept Otolaryngol Head & Neck Surg, D-8000 Munich, Germany
[5] Univ Freiburg Klinikum, Inst Pathol, Freiburg, Germany