Author response: Assessment of nodal staging and risk factors for nodal involvement in gallbladder cancer

Anita Balakrishnan

Department of Hepatopancreatobiliary Surgery, Cambridge University Hospitals NHS Foundation Trust, University of Cambridge, Cambridge, UK; Department of Surgery, University of Cambridge, Cambridge, UK

Petros Barmpounakis

Cambridge Clinical Trials Unit—Cancer Theme, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK; Department of Statistics, Athens University of Economics and Business, Athens, Greece

Nikolaos Demiris

Cambridge Clinical Trials Unit—Cancer Theme, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK; Department of Statistics, Athens University of Economics and Business, Athens, Greece

Bodil Andersson

Department of Surgery, Lund University, Skane University Hospital, Lund, Sweden

Alejandro Brañes

Department of Hepatopancreatobiliary Surgery, Hospital Sotero del Rio, Puente Alto, Chile

Xavier de Aretxabala

Department of Digestive Surgery, Hepato-Pancreato-Biliary Surgery Unit, Surgery Service, Gallbladder Consortium Chile, Sotero del Rio Hospital and Clinica Alemana, Santiago, Chile

Malin Sternby Eilard

Transplantation Centre, Sahlgrenska University Hospital, and Department of Surgery, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden

Paul Gibbs

Department of Hepatopancreatobiliary Surgery, Cambridge University Hospitals NHS Foundation Trust, University of Cambridge, Cambridge, UK; Department of Surgery, University of Cambridge, Cambridge, UK

Simon J F Harper

Department of Hepatopancreatobiliary Surgery, Cambridge University Hospitals NHS Foundation Trust, University of Cambridge, Cambridge, UK; Department of Surgery, University of Cambridge, Cambridge, UK

Emmanuel L Huguet

Department of Hepatopancreatobiliary Surgery, Cambridge University Hospitals NHS Foundation Trust, University of Cambridge, Cambridge, UK; Department of Surgery, University of Cambridge, Cambridge, UK

Asif Jah

Department of Hepatopancreatobiliary Surgery, Cambridge University Hospitals NHS Foundation Trust, University of Cambridge, Cambridge, UK; Department of Surgery, University of Cambridge, Cambridge, UK

Vasilis Kosmoliaptsis

Department of Hepatopancreatobiliary Surgery, Cambridge University Hospitals NHS Foundation Trust, University of Cambridge, Cambridge, UK; Department of Surgery, University of Cambridge, Cambridge, UK

Javier Lendoire

Department of Surgery, University of Buenos Aires, Hospital Dr Cosme Argerich, Buenos Aires, Argentina

Siong S Liau

Department of Hepatopancreatobiliary Surgery, Cambridge University Hospitals NHS Foundation Trust, University of Cambridge, Cambridge, UK; Department of Surgery, University of Cambridge, Cambridge, UK

Shishir Maithel

Division of Surgical Oncology, Lurie Comprehensive Cancer Centre, Northwestern University, Chicago, USA

Jack L Martin

Department of Hepatopancreatobiliary Surgery, Cambridge University Hospitals NHS Foundation Trust, University of Cambridge, Cambridge, UK; Department of Surgery, University of Cambridge, Cambridge, UK

Colin Noel

Gastrointestinal Surgery and Hepatopancreatobiliary Surgery, Department of Surgery, University of the Free State, Bloemfontein, South Africa

Raaj K Praseedom

Department of Hepatopancreatobiliary Surgery, Cambridge University Hospitals NHS Foundation Trust, University of Cambridge, Cambridge, UK; Department of Surgery, University of Cambridge, Cambridge, UK

Alejandro Serrablo

Department of Hepatopancreatobiliary Surgery, Miguel Servet University Hospital, Zaragoza, Spain

Volkan Adsay

Department of Pathology, Koç University Hospital, Istanbul, Turkey; Department of Pathology, Koç University Research Centre for Translational Medicine (KUTTAM), Istanbul, Turkey

the OMEGA Study Investigators