Compared to other soft tissue sarcomas (STSs), myxoid liposarcomas (MLSs) are exquisitely radiosensitive. The clinicopathological response following pre-operative radiotherapy at 50 Gy/25# in MLS might be due to radiation induction vascular damage. Here we report initial results in using multiparametric MRI (diffusion-weighted imaging, pharmacokinetic modelling and T2* measurements) to evaluate MLS response during and after preoperative RT. Dynamic contrast-enhanced examinations demonstrated both heterogeneous and homogeneous enhancement patterns. The tissue enhancement curve was monotonically-increasing in all cases, suggesting a distinct vascular pattern. Permeability and perfusion decreases from baseline in responders show Ktrans and IAUGC60 can potentially predict response.