1. Department of Plastic and Reconstructive SurgeryUniversity Medical Center Utrecht Utrecht The Netherlands
2. Department of PathologyUniversity Medical Center Utrecht Utrecht The Netherlands
3. Department of PathologyRadboud University Medical Center Nijmegen The Netherlands
4. Diagnostic Laboratory and PathologyPrincess Máxima Center for Pediatric Oncology Utrecht The Netherlands
5. Department of NeurosurgeryUniversity Medical Center Utrecht Utrecht The Netherlands
6. Department of Orthopedic SurgeryLeiden University Medical Center Leiden The Netherlands
7. Department of Solid TumorsPrincess Máxima Center for Pediatric Oncology Utrecht The Netherlands
8. Department of Surgical OncologyErasmus Medical Center Cancer Institute Rotterdam The Netherlands