title: [Microwave tumor ablation. New devices, new applications?].
abstract: OBJECTIVE
  The majority of patients with hepatic malignancies are not amenable to surgical resection. In some of these cases minimally invasive ablative therapies are a treatment option.
  
  
  METHODS
  Besides radiofrequency ablation, the most common ablative therapies are cryoablation, laser ablation and microwave ablation.
  
  
  METHODS
  The classic fields of application of microwave ablation are the treatment of malignancies of the liver, kidneys and lungs. Furthermore, cases of treatment of bone tumors and tumors of the adrenal gland have been reported as well as treatment of secondary hypersplenism.
  
  
  METHODS
  The manufacturers of microwave systems pursue different strategies to reach an optimal ablation zone, such as water or gas cooling of the antenna, the simultaneous use of different antennas or an automatic modulation of the microwave energy and frequency.
  
  
  RESULTS
  In contrast to other tumor ablation methods microwave ablation causes a direct heating of a tissue volume, thus this method is less vulnerable to the cooling effect of vessels in the ablation zone. Moreover the electric conductivity of the treated tissue does not influence microwave radiation so that microwave ablation has advantages for the treatment of high-resistance organs, such as the lungs or bone. Some publications have shown that microwave ablation causes larger ablation zones in less time in comparison to radiofrequency ablation.
  
  
  CONCLUSIONS
  Classic indications for microwave ablation are the treatment of malignancies of the liver, lungs and kidneys. Initial technical problems have been solved, so that an increasing significance of the microwave ablation among the ablative therapies is to be expected.
authors.affiliation: Abteilung für Diagnostische und Interventionelle Radiologie, Universitätsklinikum Tübingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Deutschland. ruediger.hoffmann@med.uni-tuebingen.de
authors.forename: R
authors.initials: R
authors.lastname: Hoffmann
authors.forename: H
authors.initials: H
authors.lastname: Rempp
authors.forename: S
authors.initials: S
authors.lastname: Clasen
mesh_terms: D004598:Electrosurgery / Q000295:instrumentation* / Q000379:methods*; D004867:Equipment Design; D006801:Humans; D008872:Microwaves / Q000627:therapeutic use*; D009369:Neoplasms / Q000628:therapy*