What is the best treatment approach for a patient with metastatic breast cancer that has spread to the liver?

Treatment Approach for Metastatic Breast Cancer with Liver Metastases

A multimodal approach combining systemic therapy with consideration for surgical resection offers the best survival outcomes for patients with metastatic breast cancer that has spread to the liver, particularly in highly selected patients with limited disease. 1

Survival Outcomes

• Without intervention, median survival for breast cancer patients with liver metastases ranges from 3-15 months 2
• With surgical resection, survival rates at 1,3, and 5 years can reach 90%, 65.9%, and 53%, respectively, in carefully selected patients 3
• Combination chemotherapy has improved median survival from 5 months (1950s) to 14 months (1970s) and continues to improve with modern regimens 4
• Locoregional therapies like radiofrequency ablation (RFA) show survival rates at 1,3, and 5 years of 83%, 49%, and 35%, respectively 3

Treatment Algorithm

Step 1: Initial Assessment and Referral

• All patients with breast cancer liver metastases should be referred to a tertiary center with expertise in hepatic resections and multidisciplinary management 1
• Verify HER2 status to determine eligibility for targeted therapies like trastuzumab 5
• Assess extent of disease (liver-limited vs. extrahepatic) as this significantly impacts treatment approach 1, 2

Step 2: Systemic Therapy Considerations

• Systemic therapy (chemotherapy and/or hormonal therapy) remains the primary treatment approach for metastatic breast cancer 6, 2
• Treatment should be tailored based on molecular subtype:
  • Hormone receptor-positive: Consider endocrine therapy 6
  • HER2-positive: Include HER2-targeted therapy (e.g., trastuzumab) 5
  • Triple-negative: Chemotherapy is the mainstay 6

Step 3: Evaluation for Local Therapies

• Consider surgical resection for patients meeting these criteria:

  • Good performance status 1
  • Feasibility of complete resection 1
  • No uncontrolled extrahepatic disease (except isolated bone metastases controllable with radiation or isolated pulmonary metastases) 1
  • Disease stability or response to systemic therapy 7
  • Normal liver function with ability to preserve at least 30% of liver volume 1

• Consider radiofrequency ablation (RFA) for:

  • Tumors <3 cm in diameter 8
  • Patients who are not surgical candidates 8
  • Tumors not located near major vessels 8

• Other locoregional options include:

  • Transarterial chemoembolization (TACE): Median overall survival of 15.3 months 9
  • Transarterial radioembolization (TARE): Better local control at 3 months (78.9% vs. 68.7% for TACE) but lower overall survival (11.9 months) 9

Important Considerations and Pitfalls

• Timing of surgical consultation is critical: Surgeons should evaluate patients before chemotherapy begins to properly visualize all metastases, as responsive lesions may become difficult to locate after treatment 1
• Avoid prolonged chemotherapy before surgical evaluation: Extended chemotherapy can cause liver steatosis and hepatocyte damage, compromising post-resection liver function 1
• Disease-free interval matters: Patients who develop liver metastases >24 months after breast surgery have significantly better 5-year survival (60% vs. 0%) after liver resection 10
• Surgical approach differs from colorectal metastases: Unlike colorectal cancer where surgery is primary and chemotherapy is adjuvant, in breast cancer liver metastases, systemic therapy is primary and surgery is considered adjuvant 1
• Consider immunologic benefits: Reducing tumor burden through local therapies may provide immunologic benefits and increase chemotherapy effectiveness 8

Prognostic Factors

• Factors associated with better outcomes include:
  • Liver-only metastases or liver plus bone metastases 4
  • Good performance status 4
  • Normal liver function tests (bilirubin, LDH, SGOT) 4
  • Longer interval between primary breast cancer diagnosis and development of liver metastases 10
  • Response to systemic therapy 7
  • Lower nodal burden in the primary breast cancer (N0-N1 vs. N1b-N2) 7