1. Department of Oncology; Institute of Clinical Sciences, Sahlgrenska Cancer Center, Sahlgrenska Academy, University of Gothenburg; Gothenburg Sweden
2. Department of Clinical Pathology and Cytology; Sahlgrenska University Hospital; Gothenburg Sweden
3. Department of Otolaryngology; Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg; Gothenburg Sweden
4. Division of Clinical Cancer Epidemiology; Department of Oncology; Institute of Clinical Sciences, Sahlgrenska Academy at Gothenburg University; Gothenburg Sweden
5. Regional Cancer Center (West); Western Sweden Health Care Region; Sahlgrenska University Hospital; Gothenburg Sweden
6. Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Cancer Center, Sahlgrenska Academy, University of Gothenburg; Gothenburg Sweden