1. Cancer Registry of Norway, Oslo University Hospital Oslo Norway
2. Oslo Centre for Biostatistics and Epidemiology Oslo University Hospital Oslo Norway
3. Institute for Cancer Research Oslo University Hospital Oslo Norway
4. Department of Pathology Akershus University Hospital Lorenskog Norway
5. Institute of Clinical Medicine University of Oslo Lorenskog Norway
6. Institute for Basic Medical Sciences University of Oslo Oslo Norway
7. Department of Preventive Medicine, Keck School of Medicine University of Southern California Los Angeles California
8. Department of Life Sciences and Health Oslo Metropolitan University Oslo Norway