Liver Metastases
Summary of Key Points
Diagnostic and Preoperative Evaluation
• Contrast-enhanced computed tomography is the most widely used imaging modality for detection of liver metastases, operative planning, and postoperative surveillance, with a sensitivity of 93% and a specificity of 100%.
• Percutaneous liver biopsy is rarely indicated.
• Underlying liver function and preoperative chemotherapy influence the minimum size of the future liver remnant after resection.
• Contraindications to resection of liver metastases have evolved such that tumor size and number are less important than obtaining an R0 resection. Resection may also be considered for patients with resectable extrahepatic metastases.
Management of Colorectal Liver Metastases
• Improvements in surgical technique and perioperative management have allowed for safer hepatic resections.
• Hepatic resection is the first-line treatment of liver metastases, with 5-year survival rates between 25% and 58%.
• Survival after resection of liver metastases is influenced by the following risk factors: node-positive primary cancer, disease-free interval, tumor number, tumor size, number of metastases, and preoperative carcinoembryonic antigen level.
• Preoperative systemic therapy, although helpful in identifying patients most likely to benefit from resection of liver metastases, is associated with hepatotoxicity and may affect postresection hepatic regeneration.
• Fluorouracil, oxaliplatin, and irinotecan-based perioperative chemotherapy regimens are most commonly used in the adjunctive treatment of liver metastases.
• In approximately 20% of patients with initially unresectable liver metastases, the metastases may become resectable after administration of neoadjuvant chemotherapy.
• Portal vein embolization and the two-staged hepatectomy are also strategies for improving the resectability of initially unresectable liver metastases.
• Unresectable liver metastases can be managed with systemic therapy and/or a variety of liver-directed techniques such as radiofrequency ablation, microwave ablation, cryotherapy, hepatic artery infusion, or yttrium-90 radioembolization.
