1. Department of Surgery, Erasmus MC Cancer Institute, Rotterdam, the Netherlands
2. Department of Surgery, Leiden University Medical Center, Leiden, the Netherlands
3. Department of Oncology, Leiden University Medical Center, the Netherlands
4. Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, the Netherlands
5. Department of Biostatistics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
6. Department of Epidemiology, Erasmus MC University Medical Center, Rotterdam, the Netherlands