[1] Ludwig Maximilians Univ Munchen, Dept Radiat Oncol, Munich, Germany
[2] Ludwig Maximilians Univ Munchen, Dept Med Phys, Munich, Germany
[3] Massachusetts Gen Hosp, Dept Radiat Oncol, Boston, MA 02114 USA
[4] Univ Lyon, Univ Lyon 1, CNRS, UMR 5220,INSERM,U1044,INSA Lyon,CREATIS, Lyon, France
[5] Aarhus Univ Hosp, Dept Oncol, Aarhus, Denmark