1. Department of Gastroenterological Oncology Maria Sklodowska‐Curie Memorial Cancer Centre and Institute of Oncology Warsaw Poland
2. Department of Gastroenterology, Hepatology and Oncology Medical Centre for Postgraduate Education Warsaw Poland
3. Gastroenterology Department Dr. Balmis General University Hospital Alicante Spain
4. Department of Clinical Medicine Miguel Hernández University Alicante Spain
5. ISABIAL Alicante Spain