High-Volume Dilution of Drug-Eluting Beads Reduces Severe Pain After DEB-TACE: A Single-Center Retrospective Study

Abdominal pain is the most frequent consequence of postembolization syndrome (PES) after drug-eluting bead transarterial chemoembolization (DEB-TACE). The analgesic impact of an easily modifiable intraprocedural factor-microsphere suspension dilution, remains unclear. We evaluated whether high-fold dilution during DEB-TACE reduces early postprocedural pain and severe pain risk without compromising short-term response and safety.

This single-center retrospective cohort study included 362 patients with hepatocellular carcinoma who underwent DEB-TACE. The patients were divided into conventional dilution (Group A, n = 103), 30-50-fold dilution (Group B, n = 127), and > 50-fold dilution (Group C, n = 132). The outcomes included a maximum visual analog scale (VAS) pain score within 72 hours and moderate-to-severe (VAS score ≥ 4) and severe (VAS score ≥ 7) pain scores. Associations were tested through Spearman correlation and trend tests. Univariable and multivariable logistic regression were used to estimate adjusted odds ratios (ORs) for severe pain. Short-term tumor response was also assessed according to mRECIST at 1-3 months after the index procedure.

The maximum 72-hour VAS score decreased with increasing dilution (median [interquartile range]: 6.0 [4.0-10.0] vs. 4.0 [2.0-5.0] vs. 0.0 [0.0-4.0]; P < 0.001). The prevalence of moderate-to-severe pain decreased from 77.7% to 56.7% and 28.8%, respectively, and that of severe pain decreased from 48.5% to 10.2% and 6.8%, respectively (Groups A-C). Dilution correlated with lower pain severity (ρ = -0.636; P < 0.001). Multivariate analysis revealed that compared with Group A, Groups B and C had lower odds of severe pain (OR 0.12 and 0.07; both P < 0.001). Subsegmental superselective catheterization (OR 0.45; P = 0.024) and intra-arterial lidocaine (OR 0.53; P = 0.041) were protective, whereas tumor proximity to the liver capsule increased the risk (OR 1.99; P = 0.024). Short-term tumor response also differed across groups, with the objective response rate increasing from 40.8% in Group A to 56.7% in Group B and 58.3% in Group C (P = 0.015).

High-fold microsphere suspension dilution during DEB-TACE was associated with reduced early postprocedural abdominal pain without compromising short-term laboratory safety.