Locoregional Approaches for Breast Cancer Liver Metastases: A Review

The liver is involved in 30%-50% of patients with metastatic breast cancer and, when it becomes a dominant site of disease, portends survival inferior to bone- or soft-tissue-predominant metastasis. Systemic therapy—endocrine, HER2-directed, cytotoxic, and antibody-drug conjugates—remains the backbone of care for metastatic breast cancer. Most (> 95%) patients with breast cancer liver metastases (BCLM) harbor extrahepatic disease. Thus, the role of locoregional approaches for BCLM is limited. Moreover, given the heterogeneity of retrospective studies, selection bias, and lack of high level evidence, the survival benefit of locoregional therapies for BCLM remains inconclusive. On the other hand, locoregional therapy may be valuable for durable local control, symptom palliation, and, in highly selected oligometastatic patients, potentially prolonged disease-free intervals. This review surveys the four principal locoregional modalities for BCLM: surgical resection, ablation, transarterial therapies (chemoembolization and yttrium-90 radioembolization), and stereotactic body radiotherapy. Across all modalities the evidence is dominated by retrospective and case-matched series. Case-matched surgical cohorts report 5-year overall survival rates of 50–69% in rigorously selected patients, yet a controlled comparison found no survival advantage over medical therapy. Modality choice should be multidisciplinary and biology-informed, weighing molecular subtype, hepatic tumor burden, extrahepatic disease, and response to systemic therapy. Further prospective studies are needed to define the optimal role and sequencing of these interventions.