1. a Department of Surgical Oncology, Leiden University Medical Center, Leiden, The Netherlands
2. b Department of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, The Netherlands
3. d Department of Medical Oncology, Erasmus MC–Daniel Den Hoed Cancer Center, Rotterdam, The Netherlands;
4. e Breast Unit, Department of Surgery, Athens University Medical School, Athens, Greece;
5. f Department of Medical Oncology, U.S. Oncology Research, The Woodlands, Texas, USA;
6. g Department of Medical Oncology, The University of Birmingham, Birmingham, United Kingdom;
7. h Department of Obstetrics and Gynecology, University Hospital Freiburg, Freiburg, Germany;
8. c Department of Medical Statistics, Leiden University Medical Center, Leiden, The Netherlands;
9. i Department of Internal Medicine, University Hospital Leuven, Belgium.