The impact of treatment intent on overall survival after radiofrequency ablation of colorectal cancer liver metastases: The Royal Marsden Hospital experience.

Abstract

622 Background: 50% of patients with colorectal cancer will develop liver metastases (CLM), for many patients this will be the first and only site of metastatic disease. A minority of the patients will undergo surgical resection with curative intent, the remainder may be offered treatment with chemotherapy and local ablative techniques. Radiofrequency ablation (RFA) is increasingly used to treat patients deemed unsuitable for surgery, as an adjunct to or holding procedure before hepatic resection or for patients with recurrent disease. In addition some centres use RFA in the palliative setting. The aim of this study was to determine survival outcomes according to RFA treatment intent in patients with CLM. Methods: Clinical characteristics and survival outcomes of all patients with CLM treated with RFA between 2005-2011 were recorded. Patients were grouped according to the intent with which they underwent their first RFA procedure, namely "curative intent", "holding intent" or "palliative intent". Overall survival was compared between the groups using Kaplan-Meier survival analysis and Log Rank testing. Results: A total of seventy eight pts with CLM (M:F= 44:34), age (median=66, range 43-65 years), who underwent their first RFA procedure between 2005 and 2011 were identified. Thirty pts underwent RFA as a curative procedure (38%), 18 (23%) as a “holding procedure” before hepatic resection and 30 (38%) as a palliative procedure. The median OS for all patients was 25 months after first RFA treatment. Log Rank test showed survival was significantly different according to treatment intent; patients who underwent RFA as a holding procedure before hepatic resection had improved survival over those who underwent RFA with curative intent, who in turn had improved survival over those who underwent RFA with palliative intent (47 vs. 32 vs. 16 months, p = <0.001). Conclusions: Our study demonstrates that patients do best if RFA is used as neo-adjuvant treatment prior to hepatic resection, compared to when it is used as curative or palliative procedure. Careful selection of pts is required to optimise outcomes for the pts receiving RFA.