CalliSpheres® drug-eluting beads transarterial chemoembolization versus conventional transarterial chemoembolization in patients with refractory liver metastases: a propensity score-matched multi-center study

CalliSpheres ® is the first domestically developed drug-eluting bead product in China. Although its therapeutic efficacy has been reported in primary liver cancer, clinical data remain limited for patients with refractory liver metastases failing standard systemic therapy, and head-to-head comparisons between CalliSpheres ® drug-eluting beads transarterial chemoembolization ( DEB-TACE) and conventional TACE (cTACE) are scarce. This study aimed to compare the efficacy and safety of the two interventional modalities for refractory liver metastases. This retrospective multi-center study enrolled patients with refractory liver metastases who received DEB-TACE or cTACE across four clinical centers between January 2018 and December 2021. Propensity score matching (PSM) was performed to balance confounding bias. Tumor response was assessed at 1, 3 and 6 months post-procedure per RECIST version 1.1 criteria. Primary endpoints included objective response rate (ORR), progression-free survival (PFS) and overall survival (OS); secondary endpoints consisted of disease control rate (DCR), quality of life (assessed via QLQ-C30), liver function parameters and adverse events. A total of 102 patients received DEB-TACE and 118 received cTACE. After PSM, 58 patients remained in each group with balanced baseline characteristics. The DEB-TACE group had significantly higher ORR at 1, 3 and 6 months than the cTACE group (58.6% vs. 34.5%, P = 0.001; 48.3% vs. 27.6%, P = 0.009; 44.8% vs. 25.9%, P = 0.038). Median PFS (10.5 vs. 6.7 months, P = 0.003) and median OS (25.2 vs. 15.7 months, P = 0.006) were significantly prolonged in the DEB-TACE group. Multivariate Cox regression analysis demonstrated that cTACE was an independent adverse risk factor for PFS (HR = 1.72, P = 0.009) and OS (HR = 1.65, P = 0.026). The degrees of postoperative day-4 elevations in ALT and AST as well as the incidence of abdominal pain were significantly lower in the DEB-TACE group (all P < 0.05). There were no grade ≥ 3 serious adverse events in either group. CalliSpheres ® DEB-TACE achieves superior ORR, PFS and OS and better safety compared with cTACE for patients with refractory liver metastases. Prospective randomized controlled trials are warranted to validate these findings.