1. Department of Medical Oncology, Metaxa Cancer Hospital of Piraeus, Piraeus, 185 37, Greece
2. First Department of Surgery, National & Kapodistrian University of Athens, Laikon General Hospital, Athens, 115 27, Greece
3. Second Propedeutic Department of Surgery, National & Kapodistrian University of Athens, Laikon General Hospital, Athens, 115 27, Greece
4. Department of Radiation Oncology, University Hospital of Crete, Voutes, Heraklion, Crete, 71110, Greece