[1] Univ Gothenburg, Sahlgrenska Univ Hosp, Sahlgrenska Acad, Dept Otorhinolaryngol Head & Neck Surg,Inst Clin, Gothenburg, Sweden
[2] Karolinska Hosp, Canc Ctr Karolinska, Dept Oncol & Pathol, Stockholm, Sweden
[3] Lund Univ, Skane Univ Hosp, Dept Oncol & Radiat Phys, Lund, Sweden
[4] Uppsala Univ, Sect Otorhinolaryngol & Head & Neck Surg, Dept Surg Sci, Uppsala, Sweden
[5] Orebro Univ Hosp, Dept Oncol, Orebro, Sweden
[6] Orebro Univ, Orebro, Sweden
[7] Linkoping Univ, Fac Hlth Sci, Dept Clin & Expt Med, Div Otorhinolaryngol, Linkoping, Sweden
[8] Umea Univ, Dept Clin Sci ENT, Umea, Sweden
[9] Sahlgrens Univ Hosp, Reg Canc Ctr Western Sweden, Gothenburg, Sweden
[10] Univ Gothenburg, Sahlgrenska Acad, Sahlgrenska Univ Hosp, Dept Oncol,Inst Clin Sci, Gothenburg, Sweden