1. Department of Otorhinolaryngology - Head and Neck Surgery; University of Helsinki and Helsinki University Hospital; P.O. Box 263, FI-00029 HUS Helsinki Finland
2. Department of Oncology; University of Helsinki and Helsinki University Hospital; P.O. Box 180, FI-00029 HUS Helsinki Finland
3. Department of Pathology; University of Helsinki, HUSLAB, and Helsinki University Hospital; P.O. Box 21, FI-00014 Helsinki Finland
4. Research Programs Unit; Translational Cancer Biology, University of Helsinki; P.O. Box 63, FI-00014 Helsinki Finland
5. Department of Surgery; University of Helsinki and Helsinki University Hospital, University of Helsinki; P.O. Box 22, FI-00014 Helsinki Finland
6. Department of Pathology; University of Helsinki and Helsinki University Hospital, University of Helsinki; P.O. Box 21, FI-00014 Helsinki Finland