The aim of this project is to study the presence of cancer-associated adipocytes in oesogastric cancers and their possible links with myosteatosis. This research project has a retrospective component, the aim of which is to analyse the body component based on imaging in patients with oesogastric neoplasia in order to determine the incidence of myosteatosis and to study the relationship with oncological and prognostic data. The second part of the project is prospective and will collect biological material (skeletal muscle, adipose tissue, tumour, blood) for histological, molecular and genomic analyses and will analyse muscle function in patients with oesogastric cancer. It will address the role of adipocytes in the tumour microenvironment of oesogastric cancer, focusing on their interactions with the observed muscle myosteatosis and prognosis. In the future, it will help to identify signalling pathways, targets and patients who could benefit from appropriate treatment.