Monitoring tumor responses to treatment using metabolic imaging can give an early indication of outcome. We show here that Deuterium Metabolic Imaging (DMI) with 2H-labelled fumarate can be used to detect early evidence of cell death following drug treatment in a pre-clinical murine lymphoma model. 2H spectra were acquired from tumors with a time resolution of 5 min, following a bolus injection of 2H-labelled fumarate. Within 48 h of etoposide treatment the rate of tumor malate production from the labelled fumarate increased significantly. Increased levels of labelled malate were also evident in spectroscopic images of the tumors.