Dr. Ioannis Hatzaras with his colleague Pericles Chrysoheris, Chief of the 1st Department of Surgery of Hygeia Hospital.

Dr. Ioannis Hatzaras with E. Christopher Ellison, Zollinger Professor of Surgery and former Chairman, Department of Surgery, Ohio State University.

Dr. Ioannis Hatzaras with his mentor John Cameron, Alfred Blalock distinguished Professor of Surgery and former Chairman, Department of Surgery at Johns Hopkins Hospital, and George Poultsides, Associate professor of Surgery, Chief of Surgical Oncology at Stanford University Medical Center.