[1] Univ Med Ctr Freiburg, Dept Radiat Oncol, Freiburg, Germany
[2] German Canc Consortium DKTK, Freiburg, Germany
[3] EORTC Headquarters, Brussels, Belgium
[4] Catharina Hosp, Dept Radiat Oncol, Eindhoven, Netherlands
[5] Univ Paris 11, Dept Radiat Oncoi, Villejuif, France
[6] Univ Manchester, Manchester Acad Hlth Sci Ctr, Christie NHS Fdn Trust, Inst Canc Sci, Manchester, Lancs, England
[7] KU Leuven Univ Leuven, Univ Hosp Leuven, Dept Radiat Oncol, Leuven, Belgium
[8] Antoni van Leeuwenhoek Hosp, Netherlands Canc Inst, Dept Radiat Oncol, Amsterdam, Netherlands
[9] Med Univ Gdansk, Dept Radiotherapy & Oncol, Gdansk, Poland
[10] Allgemeines Krankenhaus Celle, Dept Radiol, Celle, Germany
[11] Univ Zurich, Dept Radiat Oncol, Zurich, Switzerland