1 Department of Bariatric Surgery, Chelsea & Westminster Hospital, London, UK.
2 Department of Colorectal Surgery, Chelsea & Westminster Hospital, London, UK.
3 Department of Surgery and Cancer, Imperial College London, Chelsea and Westminster and the Royal Marsden Campus, London, UK.
4 Department of Colorectal Surgery, Royal Marsden Hospital, London, UK.
5 Department of Colorectal Surgery, Chelsea & Westminster Hospital, London, UK. c.kontovounisios@imperial.ac.uk.
6 Department of Colorectal Surgery, Royal Marsden Hospital, London, UK. c.kontovounisios@imperial.ac.uk.
7 Department of Surgery and Cancer, Imperial College London, Chelsea and Westminster and the Royal Marsden Campus, London, UK. c.kontovounisios@imperial.ac.uk.