Extent of Embolization as an Independent Prognostic Factor in Superselective Conventional Transarterial Chemoembolization for Hepatocellular Carcinoma.

[PURPOSE] Superselective conventional transarterial chemoembolization (ss‑cTACE) guided by angiography-multidetector CT (AMDCT) improves feeder detection but can broaden the treated territory and compromise hepatic reserve. We asked whether restricting the embolized area to <1 Couinaud sector‑equivalent is associated with better prognosis in treatment‑naïve hepatocellular carcinoma (HCC). Our primary estimand was the covariate‑adjusted hazard ratio (HR) comparing extended (≥1 sector‑equivalent) vs limited (<1 sector‑equivalent) embolization.

[PATIENTS AND METHODS] We conducted a single‑center retrospective cohort including 195 consecutive patients with newly diagnosed HCC who underwent initial ss‑cTACE/AMDCT (2010‑10‑01 to 2023‑08‑31; median age 75 years). Post‑procedural imaging classified patients as Group L (<1 sector‑equivalent; n=136) or Group E (≥1; n=59). Endpoints were progression‑free survival (PFS) and overall survival (OS); liver‑related death was modeled with cause‑specific hazards. Multivariable Cox models were prespecified as primary, with propensity‑score overlap weighting as a complementary sensitivity analysis; short‑term hepatic safety was assessed by post‑TACE ALBI within 1 month.

[RESULTS] Compared with Group L, Group E showed shorter PFS (median 7 vs 12 months; aHR 1.7, 95% CI 1.1-2.5; p =.01) and OS (median 21 vs 33 months; aHR 2.1, 95% CI 1.2-3.5; p =.003). Short‑term hepatic safety did not differ: the post‑TACE ALBI score assessed within 1 month was similar between groups (-2.1 ± 0.4 vs -2.0 ± 0.4; p =.16). In Group L, liver‑related survival exceeded OS (113 vs 57 months; p =.01). Adjusted analyses confirmed embolization extent as an independent prognostic factor beyond stage, tumor burden, location, and liver function (PFS aHR 1.7; OS aHR 2.1). Among Group L decedents, HBV/HCV was independently associated with liver‑related death (OR 6.9, 95% CI 1.8-34; p =0.009).

[CONCLUSION] During initial ss‑cTACE/AMDCT, restricting embolization to <1 sector‑equivalent was associated with longer PFS/OS and fewer liver‑related deaths, supporting treatment planning that minimizes ischemic parenchymal injury, particularly in older or vulnerable patients.