Radio-frequency ablation for treatment of NET liver metastases: assessment of utilisation at a single tertiary centre

Abstract

Introduction: Our previous study on the outcomes of radical treatment for neuroendocrine liver metastases (NET mets) found surgery the most commonly utilised therapy. Radio-frequency ablation (RFA) and trans-arterial embolisation (TAE) were only occasionally selected. Given the favourable morbidity and mortality of RFA and that surgery is palliative rather than curative for the majority, this study aims to address why surgery was selected more than RFA in the treatment of NET mets. Methods: Pre-operative imaging of patients with NET mets between 1998 to 2016 undergoing treatment in a single specialist HPB/NET centre was reviewed retrospectively againtst the interventional radiology consensus criteria for thermal ablation(CIRCE criteria). All patients were assessed at the NET MDT meeting and considered for each therapy. Interventional radiology records were checked to ensure ablation was not performed without MDT discussion. Results: Forty-seven patients were included. Thirty-nine were treated with surgical resection, two had RFA, two had TAE, and four underwent both RFA and surgery. Reasons for not qualifying for RFA included a) absolute contraindications: at least one lesion with diameter >3cm (n=24); simultaneous resection of extrahepatic disease (n=4); exophytic lesions (n=4); proximity to major hepatic vasculature (n=1) and gallbladder (n=1)· b) relative contraindications: a high number (>4) of hepatic metastases (n=4) and two lesions in close proximity(measuring >3cm in total) (n=1). Two patients eligible for RFA were treated operatively per surgeon preference. Conclusions: The majority of patients with NET mets seen in specialist centres are not appropriate for RFA if the CIRCE guidelines for ablation are followed.