1. Department of Soft Tissue/Bone Sarcoma and Melanoma, Maria Sklodowska Curie National Research Institute of Oncology, 02-781 Warsaw, Poland
2. Faculty of Medicine, Medical University of Warsaw, 02-091 Warsaw, Poland
3. Department of Pathology, Maria Sklodowska Curie National Research Institute of Oncology, 02-781 Warsaw, Poland