1. Department of Dermatology; Saarland University Medical School; Homburg/Saar Germany
2. Institute of Pathology; Saarland University Medical School; Homburg/Saar Germany
3. Department of Orthopedic Surgery; Saarland University Medical School; Homburg/Saar Germany
4. Department of Diagnostic and Interventional Radiology; Saarland University Medical School; Homburg/Saar Germany
5. Bone Tumor Reference Center at the Institute of Pathology; University Hospital Basel; Basel Switzerland