1. Department of Gastroenterological Oncology, Maria Skłodowska-Curie National Research Institute of Oncology, Warsaw, Poland
2. Department of Gastroenterology, Hepatology and Clinical Oncology, Center of Postgraduate Medical Education, Warsaw, Poland
3. Department of Head and Neck Cancer, Maria Skłodowska-Curie National Research Institute of Oncology, Warsaw, Poland
4. Department of Radiology, Maria Skłodowska-Curie National Research Institute of Oncology, Warsaw, Poland
5. Department of Pathology, Center of Postgraduate Medical Education, Warsaw, Poland
6. Department of Pathology and Laboratory Medicine, Maria Skłodowska-Curie National Research Institute of Oncology, Warsaw, Poland