1. 2nd Department of Internal Medicine – Gastroenterology, Charles University, Faculty of Medicine in Hradec Kralove, University Hospital, Hradec Kralove, Czech Republic;
2. The Royal Marsden Hospital NHS Foundation Trust, London, UK;
3. Institute of Clinical Biochemistry and Diagnostics, Charles University, Faculty of Medicine in Hradec Kralove, University Hospital, Hradec Kralove, Czech Republic