1 Department of Surgery, Orbis Medical Centre, Sittard-Geleen, P.O. Box 5500, 6130 MB, The Netherlands.
2 Department of Surgery, Orbis Medical Centre, Sittard-Geleen, P.O. Box 5500, 6130 MB, The Netherlands; Department of Surgery, Atrium Medical Centre, Heerlen, The Netherlands.
3 Department of Surgery, Orbis Medical Centre, Sittard-Geleen, P.O. Box 5500, 6130 MB, The Netherlands; Department of Surgery, Atrium Medical Centre, Heerlen, The Netherlands. Electronic address: [email protected].