Yttrium-90 radioembolization stops progression of targeted breast cancer liver metastases after failed chemotherapy

Abstract

Purpose: To determine, in an open-label, retrospective report, the safety and effectiveness of locoregional therapy with yttrium-90 ((90)Y) radioembolization for patients with progressing breast cancer liver metastases (BCLMs) despite multi-agent chemotherapy.

Materials and methods: Seventy-five patients with progressing BCLMs and stable extrahepatic disease were treated with radioembolization at a single institution. Retrospective review of a prospectively collected database was performed to evaluate clinical and biochemical toxicities, tumor response, overall survival (OS), and time to progression. Radiologic response assessments included Response Evaluation Criteria In Solid Tumors in primary index lesions and metabolic activity on positron emission tomography (PET). Univariate and multivariate analyses were performed.

Results: The mortality rate at 30 days was 4% (n = 3). Clinical toxicity and hyperbilirubinemia of grade 3 or worse occurred in 7.6% (n = 5) and 5.9% of patients (n = 4), respectively. Partial response (PR) was seen in 35.3% of patients (n = 24), stable disease (SD) in 63.2% (n = 43), and progressive disease in 1.5% (n = 1). PET imaging was available in 25 patients, and 21 (84%) had a complete response, PR, or SD. The median OS was 6.6 months (95% confidence interval [CI], 5.0-9.2 mo). The hazard ratio (HR) for OS on multivariate analysis was 0.39 (95% CI, 0.23-0.66) for tumor burden less than 25% compared with greater burden. Elevated bilirubin levels were shown to reduce OS. The HR for hepatic progression was 0.22 (95% CI, 0.05-0.98) for solitary versus multifocal disease.

Conclusions: Locoregional therapy with (90)Y radioembolization is safe and stops or delays the progression of targeted chemorefractory BCLMs. Adverse prognosticators were identified.

Figure 1

Maximum unidimensional change over the course of follow up for 68 patients. Negative values represent % decrease in tumor size and bars represent RECIST cutoffs for partial response (−30%) and progressive disease (+20%).

Figure 2

Overall Survival from the day of first treatment (n=9 patients are censored) stratified by tumor burden < 25% or ≥ 25%.

Figure 3

Time to Progression. (a) TTP in index lesions by RECIST criteria from the day of first treatment (n=3 patients had progressive disease). (b) Hepatic TTP in treated or untreated liver. Median hepatic TTP was 3.2mo (95% CI,1.2 to 8.5mo). (c) Extrahepatic TTP in distant sites. Median extrahepatic TTP was 4.1mo (95% CI,2.4 to 7.0mo).

Figure 3

Time to Progression. (a) TTP in index lesions by RECIST criteria from the day of first treatment (n=3 patients had progressive disease). (b) Hepatic TTP in treated or untreated liver. Median hepatic TTP was 3.2mo (95% CI,1.2 to 8.5mo). (c) Extrahepatic TTP in distant sites. Median extrahepatic TTP was 4.1mo (95% CI,2.4 to 7.0mo).

Figure 3

Time to Progression. (a) TTP in index lesions by RECIST criteria from the day of first treatment (n=3 patients had progressive disease). (b) Hepatic TTP in treated or untreated liver. Median hepatic TTP was 3.2mo (95% CI,1.2 to 8.5mo). (c) Extrahepatic TTP in distant sites. Median extrahepatic TTP was 4.1mo (95% CI,2.4 to 7.0mo).