Image-guided focused ultrasound ablation of breast cancer: current status, challenges, and future directions

Image-guided focussed ultrasound (FUS) ablation is a non-invasive procedure that has been used for treatment of benign or malignant breast tumours. Image-guidance during ablation is achieved either by using real-time ultrasound (US) or magnetic resonance imaging (MRI). The past decade phase I studies have proven MRI-guided and US-guided FUS ablation of breast cancer to be technically feasible and safe. We provide an overview of studies assessing the efficacy of FUS for breast tumour ablation as measured by percentages of complete tumour necrosis. Successful ablation ranged from 20% to 100%, depending on FUS system type, imaging technique, ablation protocol, and patient selection. Specific issues related to FUS ablation of breast cancer, such as increased treatment time for larger tumours, size of ablation margins, methods used for margin assessment and residual tumour detection after FUS ablation, and impact of FUS ablation on sentinel node procedure are presented. Finally, potential future applications of FUS for breast cancer treatment such as FUS-induced anti-tumour immune response, FUS-mediated gene transfer, and enhanced drug delivery are discussed. Currently, breast-conserving surgery remains the gold standard for breast cancer treatment

The Use of Animal Models in the Assessment of Tumour Vascular Disrupting Agents (VDAs)

Tumour vascular disrupting agents (VDAs) are designed to target established tumour blood vessels, with the aim of permanently shutting down tumour blood flow, thereby inducing secondary tumour cell death. The microtubule-disrupting tubulin-binding agents are the largest sub-group of low molecular weight VDAs, a number of which are in advanced clinical development. In addition, a number of putative molecular targets for VDA development are being investigated. In this chapter, we review the role of animal experiments in the pre-clinical assessment of VDAs. We start with considerations of the different rodent tumour models available for study, with an additional section on the potential of the zebrafish. We then review assays of vascular function and morphology, including the use of modern imaging techniques. Throughout, we provide examples of where the techniques have been used and summarise the results obtained. All the models and assay methods have advantages and disadvantages-here, we aim to provide some guidance on their future applications. © 2010 Springer Science+Business Media, LLC