Comparative outcomes of transarterial radioembolization in hepatocellular carcinoma patients with large tumor burden (>5 cm) vs. small tumor burden (≤5 cm).

Abstract

e16333 Background: The impact of tumor size on survival outcomes and adverse events in patients undergoing treatment for liver malignancies remains unclear. This study compares overall survival (OS) and other clinically relevant outcomes between patients with larger tumors (> 5 cm) and smaller tumors (≤5 cm) treated with transarterial radioembolization (TARE) for hepatocellular carcinoma (HCC). Methods: This retrospective cohort study used data from the global TriNetX Collaborative Network on individuals with HCC with larger ( > 5 cm) and smaller (≤5 cm) tumors treated with TARE, covering records from January 1, 2010, to December 31, 2020. Propensity score matching balanced baseline characteristics, yielding two comparable groups of 3,635 patients each. The follow-up period after TARE was four years. Patients with metastatic disease were excluded. Results: Before matching, the larger tumor cohort (n = 4,599) and smaller tumor cohort (n = 3,673) showed slight demographic differences. After matching (n = 3,635 each), the mean age was 64.9 years, with males comprising 70.5%–71%, non-Hispanic individuals 62.0%–63.1%, and White individuals 61.6%–61.8%. The OS analysis found no statistically significant difference between larger (> 5 cm) and smaller (≤5 cm) tumors (HR: 0.987, 95% CI: 0.912–1.067, p = 0.6752), with survival probabilities of 55.04% and 54.35%, respectively. The secondary analysis showed no significant differences in liver transplant rates (HR: 0.993, 95% CI: 0.895–1.101, p = 0.6444), acute hepatic failure (HR: 1.008, 95% CI: 0.925–1.096, p = 0.6820), hepatic encephalopathy and ascites (HR: 1.007, 95% CI: 0.925–1.096, p = 0.6820), or portal vein thrombosis (HR: 1.010, 95% CI: 0.897–1.137, p = 0.9387). Major adverse cardiac events (HR: 0.985, 95% CI: 0.905–1.071, p = 0.7305) and major adverse kidney events (HR: 0.986, 95% CI: 0.922–1.055, p = 0.8720) were also comparable. Across all endpoints, risks and survival outcomes remained consistent, demonstrating no statistically significant differences based on tumor size. Conclusions: TARE demonstrates comparable survival and adverse outcomes in HCC patients, irrespective of tumor size, supporting its efficacy and safety for treating both large (> 5 cm) and small (≤5 cm) tumors. Baseline characteristics (after matching). Characteristic Cohort 1 (Large Tumors) Cohort 2 (Small Tumors) P-Value Std. Difference Age at Index (Mean ± SD) 64.9 ± 9.17 64.9 ± 8.97 0.8491 0.0045 Current Age (Mean ± SD) 71.7 ± 8.9 71.8 ± 8.68 0.8716 0.0038 Male (%) 70.536% 70.977% 0.6800 0.0097 Not Hispanic or Latino (%) 62.063% 63.136% 0.3445 0.0222 White (%) 62.036% 61.788% 0.8279 0.0051 Unknown Ethnicity (%) 28.666% 28.961% 0.5670 0.0134 Female (%) 20.935% 20.882% 0.9540 0.0014 Unknown Race (%) 18.79% 18.569% 0.8098 0.0056 Hispanic or Latino (%) 9.271% 8.803% 0.4868 0.0163 Unknown Gender (%) 8.528% 8.143% 0.5525 0.0139