A.M. Covey¹, M.A. Maluccio², L. BenPorat¹, L.A. Brody¹, C.T. Sofocleous¹, G.I. Getrajdman¹, Y. Fong¹, K.T. Brown¹; ¹New York/US, ²Indianapolis/US

Purpose
The appropriate treatment algorithm for patients with unresectable hepatocellular carcinoma remains unclear. No prospective trial has shown any survival benefit to chemotherapy plus embolization over particle embolization alone. This study represents the largest contemporary series of patients treated with particle embolization for HCC. The objectives of this study were: 1) to evaluate the survival of patients treated in a standard fashion using particle embolization without the addition of chemotherapy, 2) to evaluate the prognostic factors that impact overall survival, and 3) to readdress the question of whether the addition of chemotherapeutic agents achieves any improvement in overall survival.

Material and methods
From January 1997 to December 2004, a total of 322 patients with HCC underwent 766 particle embolization procedures at our institution and were prospectively followed. Selective embolization of vessels feeding individual tumors was performed with Embospheres +/- polyvinyl alcohol (PVA) particles until stasis was achieved. Subsequent procedures were performed if follow-up imaging suggested persistent hypervascularity of the treated lesions or new lesions. Patient, tumor, and treatment characteristics were tested for their prognostic significance by univariate and multivariate analysis using the log rank and Cox proportional hazards model, respectively. A p-value of 0.05 was used to express significance.

Results
The median follow-up for the entire cohort was 22 months with a median follow-up for survivors of 20 months. The 1-year, 2- year and 3- year overall survival for all 322 patients was 70%, 46% and 32% respectively. On univariate analysis, Okuda stage I (p<0.001), absence of extrahepatic disease (p<0.001), and no portal venous involvement (p<0.001) were significant predictors of survival. Patients with solitary lesions or up to 4 discrete lesions survived longer than those patients with multifocal tumors (p<0.001). Patients with no single tumor greater than 5 cm survived longer than patients with larger tumors (p<0.001). Okuda stage, extrahepatic disease, diffuse disease (> 5 tumors), and size were independent predictors of survival on multivariate analysis. There were 36 major complications in 766 procedures.

Conclusion
Particle embolization without the addition of chemotherapy is efficacious in patients with HCC. A standard approach using well defined endpoints and diligent follow-up has improved patient outcomes. Overall survival and the predictors of survival in patients treated with particle embolization appear to be similar to predictors of survival with chemoembolization.