Yttrium-90 radioembolization in the management of intrahepatic cholangiocarcinoma: Effectiveness and safety outcomes from a multicenter study

Background : This study aimed to evaluate the effectiveness and safety of yttrium-90 (Y90) transarterial radioembolization (TARE) in patients with intrahepatic cholangiocarcinoma (ICC) across multiple tertiary centers in Saudi Arabia, and to identify prognostic factors associated with survival. Methods : This retrospective multicenter study included 20 adult patients with histologically confirmed ICC who were treated with Y90 TARE between 2016 and 2024. Patients from three centers received either resin or glass microspheres. Baseline clinical characteristics, imaging findings, treatment protocols, dosimetry parameters, and outcome measures were analyzed. Tumor response was assessed using response evaluation criteria in solid tumors criteria, and survival outcomes were calculated using Kaplan-Meier analysis. Prognostic factors were evaluated using univariate statistical tests. Results : The overall objective response rate after the first TARE was 65%, with 15% of patients achieving complete response and 50% achieving partial response. Three patients (15%) were successfully downstaged to resection. Median overall survival from diagnosis and from first TARE was 19.0 months and 12.2 months, respectively. Median progression-free survival (PFS) was 10.1 months. The 12-month survival rate was 90%, while the 5-year survival rate was 70%. An Eastern Cooperative Oncology Group (ECOG) performance status of 0 and a neutrophil-to-lymphocyte ratio (NLR ≤ 2) were significantly associated with improved PFS. Tumor volume and tumor-to-liver ratio were significant predictors of mortality (P = 0.045 and P = 0.013, respectively). No major adverse events were reported, while minor adverse events occurred in up to 45% of patients. Conclusion : Y90 TARE is a safe and effective locoregional therapy for unresectable ICC, offering promising disease control and survival benefit. Tumor burden, ECOG performance status, and NLR were identified as significant prognostic indicators. These findings support the role of TARE in the management of ICC and highlight the need for improved patient selection and further optimization of treatment dosing.