Study protocol for a multicentre international collaborative cohort study on the management and outcomes for T1 oesophagogastric cancer (CONGRESS)

Philip H. Pucher, Sivesh K. Kamarajah, Pradeep Bhandari, Natalie Blencowe, Tom Crosby, Richard P. T. Evans, Ewen A. Griffiths, Sheraz R. Markar, Nigel Trudgill, Timothy J. Underwood, James A. Gossage; on behalf of the CONGRESS collaborative