1 Department of Oesophago-Gastric Surgery, Salford Royal Foundation Trust, Salford Royal Hospital, Manchester, UK. bilal.alkhaffaf@srft.nhs.uk.
2 Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK. bilal.alkhaffaf@srft.nhs.uk.
3 Department of Oesophago-Gastric Surgery, Salford Royal Foundation Trust, Salford Royal Hospital, Manchester, UK.
4 Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.