Liver Metastasectomy and Systemic Therapy Improve Overall Survival Compared With Surgery Alone After Curative Liver Resection of Colorectal Metastases in a Developing Country (Costa Rica)

BACKGROUND: Resection of liver-isolated metastases of colorectal cancer (CRC) offers the greatest likelihood of cure. Nevertheless, recurrence rates after this procedure are high, and chemotherapy is a reasonable choice with inconclusive evidence. We aimed to determine if there is a survival difference between patients receiving systemic therapy with surgery versus surgery alone for resection of liver metastases. METHODS: From a source population of 170 patients treated in our National Centre (Centro Nacional de Cirugía Hepatobiliar, San José, Costa Rica), with liver metastases from various primary sites, we selected 51 patients with CRC who underwent hepatic resection with curative intent. We categorized patients according to the treatment received (fluoropyrimidine-based chemotherapy plus or minus monoclonal antibody and surgery v surgery alone) and then calculated the overall survival (OS) rate according to the Kaplan-Meier method. A Cox proportional hazard model was used to assess the influence of potential confounding variables on OS. RESULTS: After a median follow-up of 41.6 months, OS was significantly better for patients treated with systemic therapy (before and/or after hepatic resection) versus surgery alone (3-year OS: 66.7% v 41.7%; hazard ratio, 0.37; 95% CI, 0.15 to 0.91; log-rank test: P = .025). There were no differences among patients who underwent neoadjuvant (48.7%), perioperative (46.2%), and adjuvant therapy (5.1%). The use of systemic therapy was significantly associated with better OS after adjustment for confounding variables (hazard ratio, 0.23; 95% CI, 0.07 to 0.92; P = .03). CONCLUSION: Our findings support the use of systemic therapy (either perioperative, neoadjuvant, or adjuvant) as part of isolated hepatic metastasectomy from CRC.