Drug-eluting bead transarterial chemoembolization for hepatocellular carcinoma: does size really matter?

We aimed to compare the safety and effectiveness of 100-300 μm versus 300-500 μm drug-eluting bead transarterial chemoembolization (DEB-TACE) and to investigate the impact of tumor and feeding artery size on treatment outcome of different particle sizes in the treatment of hepatocellular carcinoma (HCC). This retrospective cohort study enrolled 234 consecutive patients who underwent TACE using 100-300 μm DEB (Group A, n=75) and 300-500 μm DEB (Group B, n=159) in a tertiary center between August 2012 and March 2017. Initial treatment response and adverse events were assessed using modified Response Evaluation Criteria in Solid Tumors (mRECIST) and National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) version 5.0, respectively. A total of 704 HCCs in 234 patients were evaluated. The average index tumor size was 3.8 cm. Multivariate analysis showed that tumor size, lobe involvement, particle size, and tumor location were significant predictive factors of complete response. The overall rate of complete response in groups A and B were 56.0% and 33.3% (P = 0.001), respectively. Group A had higher complete response rate than group B in the subgroup of BCLC B with tumor <3 cm (57.9% vs. 21.1%; P = 0.020) and subgroup of feeding artery ≥0.9 mm (55.2% vs. 30.9%; P = 0.014). There were fewer major complications in group A compared with group B (0% vs. 6.9%, P = 0.018). TACE with 100-300 μm DEB is associated with better initial treatment response and fewer major complications compared with 300-500 μm. Our study also highlights the impact of tumor characteristics on treatment outcome of different DEB size, which might help to select the optimal sphere size for TACE in the treatment of HCC.