Morphological, contrast-enhanced and spin labeling perfusion imaging for monitoring of relapse after RF ablation of renal cell carcinomas.
ABSTRACT MR perfusion imaging was applied for the assessment of completeness in the destruction of renal cell carcinomas by RF ablation (RFA) in a pilot study. An arterial spin labeling (ASL) approach was compared to conventional contrast-enhanced T1-weighted (CE-T1w) imaging. Ten patients suffering from renal cell carcinoma were treated by RFA. For the assessment of the extent of coagulation and for the detection of residual tumor, T1-weighted gradient-echo imaging, T2-weighted spin echo imaging and two different perfusion imaging techniques were performed before, 1 day and 6 weeks after RFA at 1.5 T. Perfusion imaging comprised CE-T1 weighted and FAIR-TrueFISP ASL imaging. Perfusion images recorded in the acute stage after RFA showed higher compliance to the definitive ablation volume reached after 6 weeks than T2-weighted images, which underestimated the true necrosis size. In the detection of residual tumor tissue, both modalities complimented each other. The exclusion of residual tumor tissue could more reliably be performed using perfusion-imaging methods. Both perfusion-imaging modalities showed sufficient imaging quality for post-interventional monitoring. Perfusion imaging provides a higher predictability of the completeness of tumor ablation and extent of coagulation than T2-weighted imaging alone. Since the results of the FAIR-TrueFISP sequence are promising, the administration of potentially nephrotoxic contrast media may be avoided in the respective patient cohort.
Article: Renal cell carcinoma radiofrequency ablation: evaluation of efficacy based on histological correlation.[show abstract] [hide abstract]
ABSTRACT: Percutaneous image-guided ablation with the use of radiofrequency has recently received much attention as a minimally invasive technique for the treatment of solid malignancies. Renal cell carcinomas (RCCs) were among the first extrahepatic tumours to be targeted with radiofrequency ablation (RFA). The aim of this study is to present the efficacy of RFA in RCC and the factors that have an impact on the attained necrosis with regards to the histological findings.The British journal of radiology 07/2008; 81(966):479-84. · 2.11 Impact Factor
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ABSTRACT: Targeted therapy has significantly improved the perspectives of patients with metastatic renal cell cancer (mRCC). Frequently, these new molecules cause disease stabilization rather than substantial tumor regression. As treatment options expand with the growing number of targeted agents, there is an increasing need for surrogate markers to early assess tumor response. Here, we review the currently available imaging techniques and response evaluation criteria for the assessment of tumor response in mRCC patients. For computed tomography (CT), different criteria are discussed including the Response Evaluation Criteria in Solid Tumors (RECIST), the Choi criteria, the modified Choi criteria, and the size and attenuation CT (SACT) criteria. Functional imaging modalities are discussed, such as dynamic contrast-enhanced CT (DCE-CT), dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), dynamic contrast-enhanced ultrasonography (DCE-US), and positron emission tomography (PET).Targeted Oncology 06/2010; 5(2):95-112. · 3.61 Impact Factor