1. Department of Surgery, Hospital Alemán of Buenos Aires, Buenos Aires, Argentina.
2. Department of Surgery, University of North Carolina, Chapel Hill, North Carolina, USA.
3. 2nd Department of General and Gastrointestinal Surgery, and Surgical Oncology of the Alimentary Tract, Medical University of Lublin, Lublin, Poland.
4. Department of Medicine, University of North Carolina, Chapel Hill, North Carolina, USA.