Yttrium-90 Radioembolization for Liver Malignancies: Prognostic Factors Associated with Survival

PURPOSE: To identify key prognostic clinical and imaging variables in patients undergoing yttrium-90 radioembolization (Y-90) for liver malignancies. MATERIALS AND METHODS: Patients with liver malignancies that progressed despite standard-of-care therapy were treated with Y-90 from 2002 to 2006. Baseline functional status, laboratory values, and diagnostic imaging were assessed before therapy. Imaging follow-up was performed 1 month after treatment and subsequently at 3-month intervals. Patients were followed for survival from the time of their first Y-90 treatment. RESULTS: Patients with follow-up imaging after radioembolization (N = 130) were included in this analysis. Primary malignancies included colon, neuroendocrine, and others. The following clinical variables had a significant effect on survival on multivariate analysis: Eastern Cooperative Oncology Group (ECOG) performance status (PS) greater than 0 (hazard ratio [HR], 7.98; 95% CI, 3.98-16), hepatic tumor burden of 51%-75% (HR, 2.46; 95% CI, 1.01-6.02), bilirubin level greater than 1.3 mg/dL (HR, 2.60; 95% CI, 1.27-5.34), hepatic metastases from breast cancer (HR, 2.51; 95% CI, 1.13-5.61), response on imaging based on World Health Organization (WHO) criteria (HR, 0.48; 95% CI, 0.24-0.94), and lymphocyte depression (HR, 0.56; 95% CI, 0.31-0.96). Among patients with colorectal cancer metastases to the liver, the HR for survival on univariate analysis for responders compared with nonresponders (per WHO criteria) was 0.26 (95% CI, 0.10-0.69). CONCLUSIONS: Cancer-related symptoms (ie, ECOG PS > 0), hepatic tumor burden greater than 50%, increased bilirubin levels, and hepatic metastases from breast cancer were found to be negative prognostic factors. Tumor response to therapy and lymphocyte depression were associated with favorable prognosis. Additionally, WHO response was identified to be a favorable prognostic factor in patients with colorectal cancer metastases. These findings may be useful when counseling patients regarding prognosis of their hepatic disease.