Better stratification of patients with esophageal cancer is therefore urgently needed. Functional magnetic resonance imaging techniques (MRI) can provide in vivo, quantitative information on tumor biology and may prove to be a useful non-invasive tool for this purpose. In this project, ultra-small superparamagnetic particles of iron oxide (USPIO) enhanced MRI using ferumoxytol (Rienso®), diffusion weighted MRI (DWI) and T2* MRI will be developed, both in terms of improvement of acquisition and data processing techniques.