Perkutane Thermoablation von Nierentumoren

Abstract

Due to modern examination techniques such as multidetector computed tomography and high-field magnetic resonance imaging, the detection rate of renal neoplasms is continually increasing. Even though tumors exceeding 4 cm in diameter rarely metastasize, all renal lesions that are possible neoplasms should be treated. Traditional treatment techniques include radical nephrectomy or nephron-sparing resection, which are increasingly performed laparoscopically. Modern thermal ablation techniques such as hyperthermal techniques like radiofrequency ablation RFA, laser induced thermal ablation LITT, focused ultrasound FUS and microwave therapy MW, as well as hypothermal techniques (cryotherapy) may be a useful treatment option for patients who are unfit for or refuse surgical resection. Cryotherapy is the oldest and best known thermal ablation technique and can be performed laparoscopically or percutaneously. Since subzero temperatures have no antistyptic effect, additional maneuvers must be performed to control bleeding. Percutaneous cryotherapy of renal tumors is a new and interesting method, but experience with it is still limited. Radiofrequency ablation is the most frequently used method. Modern probe design allows volumes between 2 and 5 cm in diameter to be ablated. Due to hyperthermal tract ablation, the procedure is deemed to be safe and has a low complication rate. Although there are no randomized comparative studies to open resection, the preliminary results for renal RFA are promising and show RFA to be superior to other thermal ablation techniques. Clinical success rates are over 90 % for both, cryo- and radiofrequency ablation. Whereas laser induced thermal therapy is established in hepatic ablation, experience is minimal with respect to renal application. For lesions of more than 2 cm in diameter, additional cooling catheters are required. MR thermometry offers temperature control during ablation. Microwave ablation is characterized by small ablation volumes and plays a role as a coagulation tool during resection. Focused ultrasound is the only non-invasive method, but it is still experimental.

Symptomatic Post-Discectomy Pseudocyst after Endoscopic Lumbar Discectomy

“…Also, contrary to the transforaminal approach, the interlaminar approach expose more PLL and during endoscopic surgery, heat from radiofrequency (RF) cautery or laser coagulation can cause inflammation. Although irrigation is used throughout such surgery, previous reports on cancer treatment have revealed that the intraoperative RF thermal injury can be significant 30,31,50) . If the pseudocyst's internal space connects with the epidural or extraforaminal space, there are no massive effects or clinical symptoms such as low back pain and/or leg pain.…”

Fortschritte im Staging des Nierenzellkarzinoms mittels hochauflösender Bildgebung

“…Diese Verfahren werden vor allem bei Rezidivtumoren mit lokalen Verwachsungen und allgemein schlecht operablen Patienten eingesetzt. Es ist jedoch heute schon klar, dass diese Verfahren auch bei resektablen Patienten eine wertvolle Alternative darstellen [13]. In welchem Umfang diese Verfahren einen Einfluss auf das tumorfreie Überleben der Patienten hat, wird derzeit untersucht.…”

Erste In-vitro-Anwendung katheter- und magnetgesteuerter ferromagnetischer Polymerfilamente aus Nanopartikeln mit hitzeinduzierter Partikelabgabe unter Einsatz des Stereotaxis-Niobe®-Systems

“…Minimalinvasive Ansätze zur Tumorbehandlung wie die laserinduzierte Thermotherapie (LITT) [1], Kryoablation [2], Radiofrequenzablation (RFA) [3,4] und thermische Ablation durch Induktionserhitzung [5] nehmen an klinischer Bedeutung zu. Neuere Konzepte versuchen auch den Einsatz von Ferrofluiden in der Tumortherapie zu etablieren [6].…”