Supplementary Material for: Impact of Procedural Quality on Outcomes of Transarterial Chemoembolization for Hepatocellular Carcinoma: A Multicenter Study

Objectives: Transarterial chemoembolization (TACE) is the primary treatment modality for intermediate-stage hepatocellular carcinoma (HCC). However, the lack of standardization to optimal technique leads to a wide variation in outcomes. This study aimed to evaluate the impact of procedure quality of TACE on HCC management. Materials and Methods: This multicenter retrospective cohort study included HCC patients with ≤4 tumors (maximum diameter ≤7 cm) treated with TACE monotherapy as first-line treatment between January 2009 and December 2022. Patients were classified into precision TACE and non-precision TACE groups based on adherence to predefined technical criteria encompassing angiography, catheterization, embolic agents, embolization endpoints, and assessment.The procedural quality further stratified using a scoring system (where points were deducted for technical deficiencies). The primary outcome was objective response rate (ORR) after first TACE (first-ORR) based on modified Response Evaluation Criteria in Solid Tumors. Secondary outcomes included overall ORR, progression-free survival (PFS), overall survival (OS), and safety profiles. Results: The analysis included 3059 patients (median age, 58.00 years [IQR: 49.00-66.00]; 2592 males [84.7%]) with 2286 patients included in precision TACE and 773 patients included in non-precision TACE group. First-ORR was 59.4% (1359/2286) in the precision TACE group versus 47.0% (363/773) in the non-precision TACE group (P<0.001), with overall ORR of 70.6% (1615/2286) versus 59.8% (462/773) (P<0.001). Median PFS was 14.00 months (IQR: 7.13-32.80) versus 10.80 months (IQR: 5.00-25.30) (HR=0.787 [95% CI: 0.719-0.861], P<0.001), and median OS was 33.63 months (IQR: 16.13-78.21) versus 26.37 months (IQR: 13.00-55.57) (HR=0.792 [95% CI: 0.716-0.876, P<0.001). The quality scoring system demonstrated a direct correlation between procedural quality and treatment response. Patients in precision TACE group had lower rates of hepatobiliary toxicity (elevated total bilirubin, 17.4% [398/2286] vs. 33.8% [261/773], P<0.001). Conclusions: Precision TACE was associated with improved outcomes and safety in HCC. The proposed scoring system correlates with treatment outcomes, suggesting its utility as a quality assessment tool for TACE procedures.