PMD49 The Potential Role of Magnetic Resonance Imaging (MRI) in Axillary Node Assessment of Early Breast Cancer: An Economic Evaluation

Abstract

THE POTENTIAL ROLE OF MAGNETIC RESONANCE IMAGING (MRI) IN AXILLARY NODE ASSESSMENT OF EARLY BREAST CANCER: AN ECONOMIC EVALUATION Meng Y1, Ward SE1, Cooper K1, Harnan SE1, Wyld L2 1University of Sheffield, Sheffield, UK, 2Royal Hallamshire Hospital, Sheffield, UK OBJECTIVES: Surgical techniques including sentinel lymph node biopsy (SLNB) and 4-node sampling (4-NS) are currently used for axillary nodal assessment of early breast cancer (EBC) in the UK. Such procedures are associated with adverse effects, (AEs), in particular scarring, pain, general anaesthesia and occasional lymphoedema which may impact on long term quality of life. Magnetic resonance imaging (MRI) is a non-invasive technique offering the potential to avoid such AEs. A range of MRI techniques, including USPIO (ultrasmall superparamagnetic iron oxide contrast agent)-enhanced and gadolinium-enhanced MRI exist, however diagnostic accuracy of these techniques may be lower than for surgical techniques. An economic evaluation was undertaken to compare MRI with surgical techniques for assessment of axillary lymph node metastases in patients with EBC. METHODS: The costs and benefits of replacing SLNB or 4-NS with MRI (replacement strategy) or adding MRI before the surgical techniques (addition strategy) were modelled using discrete-event simulation in SIMUL8®. A systematic review was undertaken to obtain effectiveness outcomes of the MRI techniques, whilst resource use data and health related utilities were obtained from the literature. RESULTS: Our results predict that a replacement strategy for MRI, based on the pooled estimate of all MRI techniques, dominates the baseline SLNB and 4-NS strategies, as a result of avoiding AEs from surgical techniques. However this strategy leads to more false-positive and false-negative cases. The MRI addition strategy may also be cost-effective, but is subject to greater uncertainty. USPIO-enhanced MRI produces the most favourable cost effectiveness ratio, but the evidence is based on studies with small patient numbers. CONCLUSIONS: These results suggest that there is a potential role for MRI in axillary node assessment of EBC. Based on current evidence USPIOenhanced MRI offers the most cost effective option, but further large studies are required to obtain high quality evidence on diagnostic accuracy.