1. Department of Medical Epidemiology and Biostatistics; Karolinska Institutet; Stockholm 171 77 Sweden
2. Department of Oncology-Pathology, Cancer Center Karolinska, Department of Oncology; Radiumhemmet, Karolinska Institutet and Karolinska University Hospital; Stockholm 17176 Sweden
3. Department of Surgical Sciences; Uppsala University; Uppsala 751 85 Sweden
4. Department of Surgery; Uppsala Academic Hospital; Uppsala 751 85 Sweden
5. Department of Cancer Screening; Stockholm-Gotland Regional Cancer Centre; Stockholm Sweden