Soft-tissue sarcomas (STS) are highly heterogeneous and, except for myxoid liposarcomas, changes in size following radiotherapy do not correlate with outcomes or histopathological response. Therefore, conventional size-based criteria fail to accurately assess response. In this study we explore the correlation and repeatability of radiomic features derived from Apparent Diffusion-Coefficient maps in a cohort of 27 patients with confirmed STS with a variety of histopathological subtypes. 19 features were identified that had good repeatability and were considered uncorrelated using hierarchical clustering. These features could be used in future studies to investigate heterogeneous response of STS to radiotherapy.