Tumor ablation techniques

Percutaneous tumor ablation techniques are now well established in the curative or palliative treatment of patients with primary or secondary malignant tumors of the liver. 

Goldberg SN (2001) Radiofrequency tumor ablation principles and techniques. Eur J Ultrasound 13(2) 129-147 Goldberg SN, Gazelle GS (2001) Radiofrequency tissue ablation physical principles and techniques for increasing coagulation necrosis. Hepatogastroenterology 48(38) 359-367... 

In this manuscript, authors focus on the technique of MW tumor ablation, the physics of the MW heating, and the technique of percutaneous interventional MW ablation. The authors give a literature survey on current clinical applications as well as results of experimental studies. 

Microwave ablation is the most recent development in the field of tumor ablation. The technique allows for flexible approaches to treatment, including percutaneous, laparoscopic, and open surgical access (Simon et al. 2005). 

Although percutaneous tumor ablation has been used in the treatment of various organs, the liver has proven to be an ideal target for this interventional treatment technique. Simultaneously, three different techniques were developed worldwide, namely cryotherapy, laser-induced thermotherapy (LITT), and radiofrequency ablation (RF). The liver plays a central role in human metabolism and so represents one of the organ systems most often affected, especially by tumorous diseases. In principle the liver can be affected by both primary malignant tumors such as hepatocellular carcinoma and, more frequently, by secondary manifestations such as liver metastases. A large number of primary tumors often cause liver metastases as well as bone, lung, and brain metas-... 

The introduction of minimally invasive thermal ablation techniques offers a safe and accurate alternative to open or laparoscopic surgery in the treatment of renal tumors. Experimental as well as clinical studies proved RF ablation to be a safe and effective treatment option for small RCCs. It is well tolerated in patients with percutaneously accessible lesions. However, the long-term outcome remains to be determined. Until then its use is limited to selected patients. Despite these limitations, published experience with renal RF ablation is continuously growing. As soon as its long-term effectiveness is proven, this technique holds the potential to replace surgery as first-line therapy in small RCCs. 

Radiofrequency is the most widespread percutaneous thermal ablation technique used in liver tumors. In the few studies in vdiich it was used in lung tumors it achieved a morphological response of up to 100% with a mean survival of up to 19.7 months (Lee et al. 2004). 

LITT is a widely used technique for minimally invasive tumor ablation throughout the body with a main focus on liver metastases. Palliative treatment options for recurrent head and neck cancer are limited by the proximity of vital vascular and neural structures and the aggressive nature of these tumors. A minimally invasive treatment modality such as interventional MR-guided LITT offers a number of potential treatment benefits. First, MR imaging provides unparalleled topographic accuracy due to its excellent soft-tissue contrast and high spatial resolution. Secondly, the temperature sensitivity of the Thermo-TurboFLASH and FLASH-2D sequences can be used to monitor the temperature elevation in the tumor and surrounding normal... 

This volume is one of the most comprehensive books offering a complete overview of our current knowledge in percutaneous tumor ablation. It covers not only all technical aspects of the sophisticated new modalities now available, but also a variety of specific clinical indications for each of these techniques within the framework of a global approach to the oncological patient. 

Boehm T, Malich A, Goldberg SN, et al (2002) Radio-frequency tumor ablation internally cooled electrode versus saline-enhanced technique in an aggressive rabbit tumor model. Radiology 222 805-813... 

As a result, image-guided techniques for percutaneous tumor ablation play a major role in the therapeutic management of HCC. While percutaneous ethanol injection (PEI) is a well-established technique for percutaneous treatment, several newer methods of tumor destruction have been developed and clinically tested over the past few years (Lencioni et al. 2004a). Among these methods, radiofrequency (RF) ablation constitutes the most extensively studied alternative to PEI (Galandi and Antes 2004). 

PEI is a well-established technique for tumor ablation (Bartolozzi and Lencioni 1996). It induces tumor necrosis as a result of cellular dehydration, protein denaturation, and chemical occlusion of tumor vessels. It is best administered by using ultrasound guidance because ultrasound allows for continuous real-time monitoring of the injection. This is crucial to realize the pattern of tumor perfusion and to avoid excessive ethanol leakage outside the lesion. Fine noncutting needles, with either a single end hole or multiple side holes, are commonly... 

Radio frequency ablation (RFA) A titanium electrode is directed to the tumor (using MRI techniques) and enough heat is generated to kill the cancerous cells. The NIH has given its imprimatur for this therapy. For further information contact the M.D. Anderson Cancer Center, Houston, at 713-792-2121 or the University Hospital of Cleveland, at 216-844-1000. 

The intent of neuroendocrine treatments is to reduce tumor burden and where necessary, eliminate or reduce the symptoms resulting from excessive production of hormones, and prolong life. Classic treatments for neuroendocrine tumors that have metastasized to the liver include surgery (resection) or transplantation and the administration of somatostatin analogues such as octreotide or lanreotide. Other approaches include ablative techniques (cryo-ablation and RFA), bland embolization, TACE, and more recently, microsphere therapy. 

Combinatorial applications of °Y and ablative techniques such as RFA and cryo-ablation may provide an option for those patients who would otherwise require surgical resection, but are at high surgical risk due to co-morbidities or prefer less invasive means of treating their disease. Y has been shown to reduce tumor burden in downstaging to transplant or resection for HCC patients [55-57], In patients presenting with tumors which are not amenable to ablative therapy due to excessive size (6-8 cm), °Y microspheres could be used to reduce these lesions (< 3 cm), followed by the use of ablative therapy to effect further response. This presumes... 

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