[1] Heidelberg Univ Hosp, Dept Radiat Oncol, Heidelberg, Germany
[2] Natl Ctr Radiat Oncol NCRO, Heidelberg Inst Radiat Oncol HIRO, Heidelberg, Germany
[3] Med Univ Vienna, Dept Radiat Oncol, Vienna, Austria
[4] Landesklinikum Wiener Neustadt, Inst Radiat Oncol & Radiotherapy, Wiener Neustadt, Austria
[5] Hosp CUF Descobertas, Dept Radiat Oncol, Lisbon, Portugal
[6] Univ Coll Hosp, Radiotherapy & Proton Beam Therapy, London, England
[7] MAASTRO Clin, Dept Med Phys, Maastricht, Netherlands
[8] Univ Hosp Birmingham, Queen Elizabeth Hosp, Dept Med Phys, Birmingham, England
[9] Skane Univ Hosp, Dept Haematol Oncol & Radiat Phys, Lund, Sweden
[10] Ludwig Maximilians Univ Munchen, Univ Hosp, Dept Radiat Oncol, Munich, Germany
[11] St Lukes Canc Ctr, Royal Surrey Fdn Trust, Radiotherapy Phys, Guildford, England
[12] Univ Chicago, Dept Radiat & Cellular Oncol, Chicago, IL USA
[13] Calvary Mater Newcastle, Radiat Oncol Dept, Waratah, Australia
[14] Univ Newcastle, Sch Informat & Phys Sci, Callaghan, Australia
[15] Univ Sydney, Inst Med Phys, Sydney, Australia
[16] Heidelberg Univ Hosp, Im Neuenheimer Feld 400, D-69120 Heidelberg, Germany