1. Department of Medical Oncology, Leiden University Medical Center , Leiden , The Netherlands
2. Department of Surgery, Leiden University Medical Center , Leiden , The Netherlands
3. Mathematical Institute, Leiden University and Department of Biomedical Data Science, Section Medical Statistics, Leiden University Medical Center , Leiden , The Netherlands
4. Department of Surgery, Admiraal de Ruyter Hospital , Goes , The Netherlands
5. Department of Surgery, Alrijne Hospital , Leiden and Leiderdorp , The Netherlands
6. Department of Medical Oncology , Reinier de Graaf Gasthuis , Delft , The Netherlands
7. Department of Internal Medicine, LangeLand Hospital , Zoetermeer , The Netherlands
8. Department of Surgery, Haaglanden Medical Center , The Hague , The Netherlands
9. Department of Surgery, Groene Hart Hospital , Gouda , The Netherlands
10. Department of Surgery, Haga Hospital , The Hague , The Netherlands
11. Department of Surgery, Diakonessenhuis , Utrecht , The Netherlands