Volumetric assessment of tumour response using functional MR imaging in patients with hepatocellular carcinoma treated with a combination of doxorubicin-eluting beads and sorafenib

Objective To prospectively assess treatment response using volumetric functional magnetic resonance imaging (MRI) metrics in patients with hepatocellular carcinoma (HCC) treated with the combination of doxorubicin-eluting beadtransarterial chemoembolization (DEB TACE) and sorafenib. Methods A single center study enrolled 41 patients treated with systemic sorafenib, 400 mg twice a day, combined with DEB TACE. All patients had a pre-treatment and 3-4 week post-treatment MRI. Anatomic response criteria (RECIST, mRECIST and EASL) and volumetric functional response (ADC, enhancement) were assessed. Statistical analyses included paired Student's t-test, Kaplan-Meier curves, Cohen's Kappa, and multivariate cox proportional hazard model. Results Median tumour size by RECIST remained unchanged post-treatment (8.3 +/- 4.1 cm vs. 8.1 +/- 4.3 cm, p=0.44). There was no significant survival difference for early response by RECIST (p=0.93). EASL and mRECIST could not be analyzed in 12 patients. Volumetric ADC increased significantly (1.32x10(-3) mm(2)/sec to 1.60x10(-3) mm(2)/sec, p<0.001), and volumetric enhancement decreased significantly in HAP (38.2 % to 17.6 %, p<0.001) and PVP (76.6 % to 41.2 %, p<0.005). Patients who demonstrated >= 65 % decrease PVP enhancement had significantly improved overall survival compared to non-responders (p<0.005). Conclusion Volumetric PVP enhancement was demonstrated to be significantly correlated with survival in the combination of DEB TACE and sorafenib for patients with HCC, enabling precise stratification of responders and non-responders.