irreversible electroporation

Irreversible electroporation (IRE), also known as non-thermal irreversible electroporation (NTIRE), is a non-invasive soft-tissue ablation technique used for tumor ablation in regions that require very high precision and preservation of surrounding collagenous structures (vessels and ducts) and a reduced susceptibility to heat sink effects.

Mechanism

In IRE electrodes are placed in tumor cells where they alter transmembrane potentials. This leads to permanent porous channels in the cell membranes causing irreversible damage and subsequently apoptosis. Apoptosis is a much more controlled way of cell death as opposed to necrosis. This is why the surrounding cells, vessels are spared.

IRE involves accurate parallel placement of at least two electrodes and is, therefore, more challenging than other ablation techniques. Other challenges include the potential need for general anesthesia due to the occurrence of whole-body muscle spasms and synchronisation with the cardiac refractory period to prevent cardiac arrhythmias, which have been described with IRE .

The major advantages of IRE are its applicability near structures that are susceptible to thermal injuries, such as bile ducts (hence its use in tumors in liver and pancreas) and vessels due to a decrease in the heat-sink effect. These advantages may provide a treatment option for tumors that would otherwise not have been candidates for ablation.

Outcomes

Follow up of IRE patient outcomes is an emerging topic of research within interventional oncology with hepatic tumors being the focus of many studies. Preliminary evidence suggests that IRE appears to mainly induce local tumor control rather than cure. A larger lesion size (> 2 cm) is associated with shorter time to progression. In addition, the type of tumor is a significant factor in prognosis with HCC having better outcomes than metastatic colorectal carcinoma .

Siehe auch:

• Transarterielle Chemoembolisation
• Radiofrequenzablation (RFA)
• Selektive interne Radiotherapie (SIRT)
• Laserinduzierte interstitielle Thermotherapie (LITT)

und weiter:

• percutaneous tumor ablation