(1)University of Freiburg- Medical Center, Department of Radiation Oncology, Freiburg, Germany;(2)Saarland University Hospital, Department of Radiation Oncology, Homburg/Saar, Germany;(3)University Hospital Mainz, Department of Radiation Oncology, Mainz, Germany;(4)Kliniken Maria Hilf, Department of Radiation Oncology, Mönchengladbach, Germany;(5)Marienhospital Stuttgart, Department of Radiation Oncology-, Stuttgart, Germany;(6)Klinikum Mutterhaus der Boromäerinnen, Department of Radiation Oncology-, Trier, Germany;(7)University Hospital Magdeburg, Department of Radiation Oncology, Magdeburg-, Germany;(8)Charité University Hospital, Department of Radiation Oncology, Berlin, Germany;(9)Offenburg St. Josefsklinik, Department of Radiation Oncology, Offenburg, Germany;(10)Helios University Hospital Wuppertal, Department of Nuclear Medicine, Wuppertal, Germany;(11)Marienhospital Stuttgart, Department of Nuclear Medicine, Stuttgart, Germany;(12)University Hospital Mainz, Department of Nuclear Medicine, Mainz, Germany;(13)Helios Kliniken Schwerin, Department of Nuclear Medicine, Schwerin, Germany;(14)Saarland University Hospital, Department of Nuclear Medicine, Homburg/Saar, Germany;(15)University of Mainz, Institute of Medical Biostatistics- Epidemiology and Informatics, Mainz, Germany;(16)University of Freiburg, Institute for Medical Biometry and Statistics, Freiburg, Germany;(17)University of Freiburg - Medical Center, Department of Radiation Oncology, Freiburg, Germany;

(1)Hirslanden Klinik Zürich, Radiotherapie, Zürich, Switzerland;(2)University Hospital of Geneva, Radiation Oncology, Geneva, Switzerland;(3)SAKK Coordinating Center, Informatics, Bern, Switzerland;(4)SAKK Coordinating Center, Coordinating Center, Bern, Switzerland;(5)Cantonal Hospital of Winterthur, Radiation Oncology, Winterthur, Switzerland;(6)Cantonal Hospital of Graubünden, Departement of Hematology/Oncology, Chur, Switzerland;(7)Inselspital- Bern University Hospital, Department of Radiation Oncology, Bern, Switzerland;(8)University Hospital of Basel, Clinic of Radiotherapy and Radiation Oncology, Basel, Switzerland;(9)Cantonal Hospital of Fribourg - HFR, Radiation Oncology, Fribourg, Switzerland;(10)Cantonal Hospital of St. Gallen, Radiation Oncology, Sst. Gallen, Switzerland;(11)Oncology Institute of Southern Switzerland, Radiation Oncology, Bellinzona, Switzerland;(12)SAKK Coordinating Center, Quality of Life Office and International Breast Cancer Study Group IBCSG Coordinating Center, Bern, Switzerland;