Local recurrence rates after radiofrequency ablation or resection of colorectal liver metastases. Analysis of the European Organisation for Research and Treatment of Cancer #40004 and #40983

Aim: The aim of this study is to describe local tumour control after radiofrequency ablation (RFA) and surgical resection (RES) of colorectal liver metastases (CLM) in two independent European Organisations for Research and Treatment of Cancer (EORTC) studies. Background: Only 10-20% of patients with newly diagnosed CLM are eligible for curative RES. RFA has found a place in daily practice for unresectable CLM. There are no prospective trials comparing RFA to RES for resectable CLM. Methods: The CLOCC trial randomised 119 patients with unresectable CLM between RFA (+/- RES) + adjuvant FOLFOX (+/- bevacizumab) versus FOLFOX (+/- bevacizumab) alone. The EPOC trial randomised 364 patients with resectable CLM between RES +/- perioperative FOLFOX. We describe the local control of resected patients with lesions <= 4 cm in the perioperative chemotherapy arm of the EPOC trial (N = 81) and the RFA arm of the CLOCC trial (N = 55). Results: Local recurrence (LR) rate for RES was 7.4% per patient and 5.5% per lesion. LR rate for RFA was 14.5% per patient and 6.0% per lesion. When lesion size was limited to 30 mm, LR rate for RFA lesions was 2.9% per lesion. Non-local hepatic recurrences were more often observed in RFA patients than in RES patients, 30.9% and 22.3% respectively. Patients receiving RFA had a more advanced disease. Conclusions: LR rate after RFA for lesions with a limited size is low. The local control per lesion does not appear to differ greatly between RFA and surgical resection. This study supports the local control of RFA in patients with limited liver metastases. Future studies should evaluate in which patients RFA could be an equal alternative to liver resection. (C) 2013 Elsevier Ltd. All rights reserved.