Transarterial embolization with a low-viscosity ethylene vinyl alcohol (EVOH) copolymer for ruptured hepatocellular carcinoma: an oncologic role beyond hemostasis

Abstract Background Ruptured hepatocellular carcinoma (r-HCC) is a life-threatening complication requiring urgent hemostasis. Transarterial embolization (TAE) is the first-line treatment, but the optimal embolic agent remains debated. This study reports on the use of a low-viscosity EVOH copolymer (Squid Peri12) in the emergency management of r-HCC. Methods Four patients presenting with r-HCC underwent emergency TAE using Squid Peri12. Diagnosis of rupture was based on clinical symptoms and characteristic imaging findings, including hemoperitoneum. TAE was performed via superselective catheterization using a DMSO-compatible microcatheter, with slow injection under fluoroscopic guidance. Tumor response was assessed using modified RECIST and volumetric analysis at 1, 3, and 6 months. Results Technical success was achieved in all cases, with immediate bleeding control and no procedure-related complications. Portal vein patency was preserved, and all patients were discharged within 3–5 days. At follow-up, all patients showed sustained devascularization and tumor shrinkage, with an average volume reduction exceeding 60% at 6 months. Two patients became eligible for curative-intent surgery after marked radiologic and biologic response, including one with AFP decline from 3500 to 27 ng/mL. A third declined surgery despite downstaging, and one demonstrated complete radiologic response without additional treatment. Conclusion TAE with low-viscosity EVOH was safe and effective in the acute setting of r-HCC, achieving rapid hemostasis and consistent tumor regression. These findings support further prospective evaluation of non-adhesive liquid embolics beyond emergent indications, including their potential oncologic role in unresectable HCC. Level of Evidence Level 4, Case Series.