1. First Department of Surgery, National & Kapodistrian University of Athens, Laikon General Hospital, Athens, Greece
2. Department of Medical Oncology, Metaxa Cancer Hospital, Athens, Greece
3. Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
4. Department of Internal Medicine, Section of Medical Oncology, National & Kapodistrian University of Athens, Attikon University Hospital, Athens, Greece
5. Molecular Oncology Unit, Department of Biological Chemistry, National & Kapodistrian University of Athens, Athens, Greece