Introduction

Abstract

There has been tremendous interest and proliferation in minimally invasive procedures to treat various types of cancer during the past decade. This can be largely attributed to an increased number of patients diagnosed with cancer each year and to the significant improvements in chemotherapy and surgical options that have lead to prolongation of survival in these patients. This translates into an ever-increasing number of patients who present with more atypical, delayed, or relatively organ specific and dominant tumor burden that is not amenable to therapies that are more traditional. Thus, nontraditional therapies, such as those that are applied in a local and regional manner, will continue to experience an increased demand. Physicians, such as Interventional Radiologists, who possess advanced image interpretation skills and safe methods to directly apply effective in situ tumorcidal therapies, will be on the leading cusp of creating and validating this evolving field. Transcatheter arterial therapies to treat liver cancer have been used for decades and exploit the intrinsic differential in hepatic tumor vasculature that allows more selective delivery of therapeutic agents to tumor thereby minimizing adverse effects on normal hepatocytes. Despite this promise, initial experiences with hepatic arterial infusional chemotherapy and chemoembolization did not deliver the anticipated results. More recently, however, given the advances in catheter-based technology, therapeutics, and delivery systems, the outcomes (ie, local control, survival, and down staging to resection) have improved considerably and there is a resurgence of interest in this approach. Ablative therapies including radiofrequency, cryotherapy, and chemicals have also been used to treat neoplasia within the liver. For example, in the case of hepatocellular carcinoma, strict adherence to patient selection criteria, improved devices, enhanced intraprocedural monitoring and postprocedural imaging surveillance have led to studies that demonstrate identical survival benefits when thermal ablation is compared with liver resection. This issue of Techniques in Vascular and Interventional Radiology is the first of a two part series on interventional oncology that will focus primarily on technical considerations and patient selection, and secondarily on the results of these therapies for patients with primary or metastatic liver cancer. In this issue, known experts in the field provide detailed and comprehensive information on the “state-of-the-art” of various stand-alone or combinatorial percutaneous image-guided transarterial and ablative therapies. In addition, important topics such as preoperative portal vein embolization, a neoadjuvant procedure proven to safely increase the eligible candidates for major hepatic resection by stimulating preoperative growth of the anticipated liver remnant, and the use of technological imaging advances such as intraprocedural computed tomography to assist real-time planning, guidance, and evaluation of existing and new hepatic vascular oncologic interventions will be reviewed. I would like to thank all the authors for their insightful and outstanding contributions to this important and timely issue of Techniques in Vascular and Interventional Radiology.