Yttrium-90 radioembolization in patients with unresectable liver metastases: determining the factors that lead to treatment efficacy.

ABSTRACT

INTRODUCTION: Locoregional treatments, such as radioembolization, can be used to treat patients with unresectable liver metastases. We aimed to determine the progression-free survival and factors that predict survival of patients with liver metastases whose response to selective internal radiation therapy (SIRT) with Y-90 was assessed by positron emission tomography-computed tomography (PET-CT). PATIENTS Our study included 78 liver cancer patients who were treated with Y-90 radioembolization. RESULTS: The post-treatment response rates were as follows 7 patients (9%) had stable disease (SD), 26 patients (33.3%) had a partial response (PR), 4 patients (5.1%) had a complete response (CR). The median hepatic progression-free survival (HPFS) was 4.4 months while median overall survival was 10.1 months. Univariate analysis revealed that HPFS is significantly affected by international normalized ratio (INR) levels and age (Hazard Ratio(HR)=0.54 (95%CI0.30-096), P=0.034, HR=1.03(95%CI1.00-1.05), P=0.051). However, only INR levels retained significance with multivariate analysis (HR=0.53 (95%CI0.30-0.93), P=0.028), while age had limited significance (HR =1.02 (95% CI1.00-1.05), P=0.051). CONCLUSIONS: We determined that Y-90 radioembolization is effective as a salvage therapy in patients with predominant liver metastases. For the first time, we showed that age and INR values reflecting the functional hepatic reserve can be used as positive predictive factors for HPFS.