Amide proton transfer imaging corrected by apparent diffusion coefficient to detect response of chemotherapy in bone and soft tissue sarcomas

Motivation: Evaluating the response to chemotherapy based on volume changes is often difficult in bone and soft tissue sarcomas; therefore, new molecular imaging techniques are required. Goal(s): To investigate whether amide proton transfer (APT) imaging combined with apparent diffusion coefficient (ADC) accurately reflects treatment efficacy in bone and soft tissue sarcomas. Approach: An MRI was performed before and after chemotherapy in 12 patients who received preoperative chemotherapy. Tumor volume, APT, and ADC were compared before and after treatment and correlated with postoperative pathology specimens. Results: Only APT imaging with ADC correction correctly reflected the effect of preoperative chemotherapy. Impact: The present study demonstrates that a new molecular imaging technique can accurately determine the efficacy of chemotherapy for bone and soft tissue sarcomas. This will help to determine the optimal course of treatment and improve patient prognosis.