1. Sao Leopoldo Mandic School of Medicine, Campinas, Brazil.
2. Gastromed Zilberstein Institute, São Paulo, Brazil.
3. Beneficencia Portuguesa Hospital, São Paulo, Brazil.
4. Gastrointestinal Surgery Division, Massachusetts General Hospital, Boston, Massachusetts, USA.
5. Colon and Rectal Surgery Department, Massachusetts General Hospital, Boston, Massachusetts, USA.
6. Harvard Medical School, Boston, Massachusetts, USA.