Addition of Y-90 radioembolization increases tumor response and local disease control in hepatocellular carcinoma patients receiving sorafenib

Purpose: To compare the treatment response and progression-free survival (PFS) in advanced hepatocellular carcinoma (HCC) patients who received sorafenib treatment either alone or combined with radioembolization (RE). Methods: Follow-up images of the patients treated within a multicenter phase II trial (SORAMIC) were assessed by mRECIST. A total of 177 patients (73 combination arm [RE + sorafenib] and 104 sorafenib arm) were included in this post-hoc analysis. Response and progression characteristics were compared between treatment arms. Survival analyses were done to compare PFS and post-progression survival between treatment arms. Multivariate Cox regression analysis was used to compare survival with factors known to influence PFS in patients with HCC. Results: The combination arm had significantly higher objective response rate (61.6% vs. 29.8%, p < 0.001), complete response rate (13.7% vs. 3.8%, p = 0.022), and a trend for higher disease control rate (79.2% vs. 72.1%, p = 0.075). Progression was encountered in 116 (65.5%) patients and was more common in the sorafenib arm (75% vs. 52.0%, p = 0.001). PFS (median 8.9 vs. 5.4 months, p = 0.022) and hepatic PFS were significantly better in the combination arm (9.0 vs. 5.7 months, p = 0.014). Multivariate analysis confirmed the treatment arm as an independent predictor of PFS. Conclusion: In advanced HCC patients receiving sorafenib, combination with RE has an additive anticancer effect on sorafenib treatment resulting in a higher and longer tumor response. However, the enhanced response did not translate into prolonged survival. Better patient selection and superselective treatment could improve outcomes after combination therapy.