1. Department of Radiation Sciences, Oncology Unit, Umeå University, Umeå, Sweden
2. International Agency for Research on Cancer, World Health Organization, Lyon, France
3. Department of Statistics, Umeå University, Umeå, Sweden
4. Deparment of Medical Biosciences, Pathology, Umeå University, Umeå, Sweden
5. Wallenberg Centre for Molecular Medicine, Umeå University, Umeå, Sweden