1. Department of Radiotherapy, Military Institute of Medicine–National Research Institute, ul. Szaserów 128, 04-141 Warsaw, Poland
2. Department of Radiotherapy, Regional Oncology Centre, ul. Bialska 104/118, 42-200 Czestochowa, Poland
3. Department of Radiotherapy I, Maria Sklodowska-Curie National Research Institute of Oncology, ul. W.K. Roentgena 5, 02-781Warsaw, Poland