1. Department of Endocrinology, Diabetes and Nutrition, Charité-Universitätsmedizin Berlin, Berlin, Germany
2. Department of Neurosurgery, University of Erlangen-Nuremberg, Erlangen, Germany
3. Department of Neurosurgery, Johannes Wesling Klinikum, Universitätsklinikum der Ruhruniversität Bochum, Minden, Germany
4. Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University Vienna, Vienna, Austria
5. Department of Neurosurgery, Medical University Vienna, Vienna, Austria
6. Department of Internal Medicine I, Division of Endocrinology and Diabetes, University Hospital Würzburg, University of Würzburg, Würzburg, Germany
7. Department of Endocrinology, Diabetes and Metabolism, University Hospital Essen, Essen, Germany
8. Vth Department of Medicine, Medical Faculty Mannheim of the University of Heidelberg, Mannheim, Germany
9. Department of Endocrinology, Diabetes and Preventive Medicine, University Hospital of Cologne, Cologne, Germany
10. Department of Internal Medicine 1, Johann Wolfgang Goethe-University Hospital, Frankfurt, Germany
11. Medicover Oldenburg MVZ, Oldenburg, Germany
12. Endokrinologikum Berlin, Berlin, Germany
13. Department of Neurosurgery, Agaplesion Diakonieklinikum Rotenburg, Rotenburg, Germany
14. Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Ludwig-Maximilians-Universität München, Munich, Germany
15. Institute of Pathology, SozialStiftung Bamberg, Bamberg, Germany
16. ENDOC Center for Endocrine Tumors, Hamburg, Germany
17. Department of Neurosurgery, University of Tuebingen, Tuebingen, Germany