[1] Univ Hosp Schleswig Holstein, Campus Kiel, Kiel, Germany
[2] Med Univ Vienna, Ctr Comprehens Canc, Radiat Oncol, Vienna, Austria
[3] Oslo Univ Hosp, Med Phys, Oslo, Norway
[4] Univ Freiburg, Div Med Phys, Dept Radiat Oncol, Fac Med,Med Ctr, Freiburg, Germany
[5] MAASTRO, Radiat Oncol, Maastricht, Netherlands
[6] Philips Res, Oncol Solut Dept, Eindhoven, Netherlands
[7] Acad Med Ctr, Brachytherapy, Amsterdam, Netherlands
[8] Univ Lubeck, Univ Hosp Schleswig, Interdisciplinary Brachytherapy Unit, Holstein Campus Lubeck, Lubeck, Germany
[9] Univ Wisconsin, Sch Med & Publ Hlth, Dept Med Phys, Madison, WI 53706 USA