[1] Haaglanden Med Ctr, The Hague, Netherlands
[2] Leiden Univ, Med Ctr, Leiden, Netherlands
[3] Copenhagen Univ Hosp, Rigshosp, Diagnost Ctr, Copenhagen, Denmark
[4] Univ Hosp Copenhagen, Copenhagen, Denmark
[5] Copenhagen Univ Hosp, Rigshosp, Copenhagen, Denmark
[6] Univ Med Ctr Utrecht, Utrecht, Netherlands
[7] Med Spectrum Twente, Enschede, Netherlands
[8] Erasmus MC, Rotterdam, Netherlands
[9] Maastricht UMC, Maastricht, Netherlands
[10] Radiotherapiegroep, Arnhem, Netherlands
[11] Erasmus Univ, Med Ctr, Rotterdam, Netherlands