Outcomes of Ablation versus Resection for Colorectal Liver Metastases

Introduction

Colorectal cancer has a rising worldwide annual incidence of close to one million. Approximately half of patients with colorectal cancer develop metastasis to the liver, with either a synchronous (10–20%) or metachronous (20–25%) presentation. Historically, patients with untreated colorectal liver metastasis (CRLM) had a median survival of less than 6 months. In contrast, the median survival for patients with unresectable disease receiving modern chemotherapeutic agents ranges from 17 to 25 months. In the current era, when feasible, complete surgical resection of CRLM in combination with systemic chemotherapy offers the only potential for cure and is considered the gold-standard treatment, with reports of 5-year survival upwards of 58%.

Abstract

Approximately half of patients with colorectal cancer develop metastasis to the liver, with either a synchronous or metachronous presentation. Complete surgical resection of colorectal liver metastasis (CRLM) offers the best potential for cure and is considered the gold-standard treatment. However, the use of ablative techniques to treat CRLM has gained greater acceptance and is increasingly utilized. While in the past cryoablation was utilized, currently thermo-ablation with either radiofrequency or microwave energy is the preferred approach to ablate CRLM. Data regarding the oncologic outcome of patients treated with ablation versus resection have been ambiguous. Evidence regarding the use and efficacy of ablation for CRLM has largely been derived from retrospective series. Most data suggest that outcomes (ie, overall and disease-free survival) following ablation are worse as compared with hepatic resection. Patients undergoing ablation, however, often have very different clinicopathologic characteristics than patients undergoing resection, making retrospective comparisons difficult to interpret. We herein review the current data on the outcomes of ablation versus resection for CRLM.

Keywords

colorectal cancer, metastasis, resection, ablation, recurrence, outcomes