Priming of Sorafenib Prior to Radiofrequency Ablation Does Not Increase Treatment Effect in Hepatocellular Carcinoma.

Preclinical studies have shown that modulation of the tumor microvasculature with anti-angiogenic agents decreases tumor perfusion and may increase the efficacy of radiofrequency ablation (RFA) in hepatocellular carcinoma (HCC). Retrospective studies suggest that sorafenib given prior to RFA promotes an increase in the ablation zone, but prospective randomized data are lacking. We conducted a randomized, double-blind, placebo-controlled phase II trial to evaluate the efficacy of a short-course of sorafenib prior to RFA for HCC tumors sized 3.5–7 cm (NCT00813293). Treatment consisted of sorafenib 400 mg twice daily for 10 days or matching placebo, followed by RFA on day 10. The primary objectives were to assess if priming with sorafenib increased the volume and diameter of the RFA coagulation zone and to evaluate its impact on RFA thermal parameters. Secondary objectives included feasibility, safety and to explore the relationship between tumor blood flow on MRI and RFA effectiveness. Twenty patients were randomized 1:1. Priming with sorafenib did not increase the size of ablation zone achieved with RFA and did not promote significant changes in thermal parameters, although it significantly decreased blood perfusion to the tumor by 27.9% (p = 0.01) as analyzed by DCE-MRI. No subject discontinued treatment owing to adverse events and no grade 4 toxicity was observed. Priming of sorafenib did not enhance the effect of RFA in intermediate sized HCC. Future studies should investigate whether longer duration of treatment or a different antiangiogenic strategy in the post-procedure setting would be more effective in impairing tumor perfusion and increasing RFA efficacy.