Multi-Parametric Quantitative MRI Assessment of Soft Tissue Sarcoma Response to Preoperative Therapy

Thirty patients with lower extremity soft tissue sarcoma were treated with preoperative chemoradiotherapy and underwent MRI exams including DCE- and DW-MRI pre-therapy, after the first cycle of therapy regimen, and after completion of therapy but before surgery. Ten patients had optimal and the other 20 had sub-optimal pathologic responses based on necrosis percentage of the surgical tumor specimens. Quantitative DCE-MRI markers and apparent diffusion coefficient (ADC) were superior to radiographic tumor size measurement in early prediction and evaluation of therapy response. Multi-parametric approach of combining DCE- and DW-MRI markers further improved early prediction of optimal vs. sub-optimal response.