Image-guided Tumor Ablation: Standardization of Terminology and Reporting Criteria

Abstract

The field of interventional oncology with use of image-guided tumor ablation requires standardization of terminology and reporting criteria to facilitate effective communication of ideas and appropriate comparison between treatments that use different technologies, such as chemical (ethanol or acetic acid) ablation, and thermal therapies, such as radiofrequency (RF), laser, microwave, ultrasound, and cryoablation. This document provides a framework that will hopefully facilitate the clearest communication between investigators and will provide the greatest flexibility in comparison between the many new, exciting, and emerging technologies. An appropriate vehicle for reporting the various aspects of image-guided ablation therapy, including classification of therapies and procedure terms, appropriate descriptors of imaging guidance, and terminology to define imaging and pathologic findings, are outlined. Methods for standardizing the reporting of follow-up findings and complications and other important aspects that require attention when reporting clinical results are addressed. It is the group's intention that adherence to the recommendations will facilitate achievement of the group's main objective: improved precision

Image-guided multipolar radiofrequency ablation of liver tumours: initial clinical results

“…Description of the results of RF ablation was based on recommendations by the International Working Group on Image-Guided Tumor Ablation [24]. Twenty-four hours after RF procedure, the technical success and early complications were assessed by a triphasic contrastenhanced CT with the following parameters: 2 ml/kg of iodinated contrast agent, rate of 3-5 ml/s, section thickness 3.0 mm, reconstruction interval 1.5 mm.…”

“…Any contrast-enhanced foci on CT and hyperintensity on T2-weighted images or non-enhancing area on contrast-enhanced MR images at the boundaries of the treated area was considered as incomplete ablation. Follow-up consisted in monitoring of tumour markers and CT or MRI scans every 3-4 months, and results were recorded according to standard criteria [24,26]. Recurrence rates were calculated from the first RF ablation to the imaging follow-up that revealed tumour progression.…”

Recent advances in multidisciplinary management of hepatocellular carcinoma

“…One advantage of MWA over RFA is that treatment outcome is not affected by the heat-sink effect of vessels in proximity to the tumor [49] . Laser ablation refers to thermal tissue destruction by conversion of absorbed light into heat [51] . The only randomized prospective study comparing laser ablation with RFA reported no significant difference in overall survival rates, with cumulative rates of 91.8%, 59.0% and 28.4% at one, three and five years respectively, without significant complications.…”

Radiofrequency ablation of small liver malignancies under magnetic resonance guidance: progress in targeting and preliminary observations with temperature monitoring

“…Description of the results of RF ablation was based on international recommendations according to standard criteria [16,23]. Follow-up consisted in MR imaging with hepato-specific contrast and monitoring of tumour markers at 1 week, 1 month and every 3 months.…”

“…Image-guided tumour ablation has been defined in distinct steps, namely planning, targeting, monitoring, controlling and follow-up [16]. The purpose of this study was to evaluate whether all these steps, including RF electrode targeting under high temporal resolution navigation and monitoring of temperature and energy deposition during RF application, can be performed effectively in small liver tumours that are detectable only with MR imaging.…”