Abstract #1227

Deng J, Miller F, Omary R, Larson A, Rhee T, Salem R, Mulcahy M, Sato K

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer death in the United States. Yttrium-90 radioembolization is an emerging HCC treatment that delivers internal radiation to lesions via catheter-directed intra-arterial administration of 90Y microspheres. Early, non-invasive, biomarkers for predicting response to 90Y therapy could greatly benefit HCC patients. Tumor size changes are the traditional criteria used to non-invasively assess HCC response, but may not correlate with therapeutic efficacy. Recent studies have demonstrated that quantitative diffusion-weighted MRI (DW-MRI) may provide sensitive clinical biomarkers for the early stratification of therapy response in brain tumors and breast metastases. However, no studies have validated DW-MRI detection of water mobility changes in HCC tissue after 90Y radioembolization. The purpose of this study was to test the hypothesis that DW-MRI can detect increased water diffusion secondary to HCC tissue alteration following 90Y therapy.