A multicentre international collaborative cohort study on the management and outcomes for T1 oesophagogastric cancer (CONGRESS). Issue 1 (January 2023) - Pucher, Philip; Kamarajah, Sivesh; Blencowe, Natalie; Griffiths, Ewen; Evans, Richard; Markar, Sheraz; Crosby, Tom; Bhandari, Pradeep; Trudgill, Nigel; Underwood, Tim; Gossage, James