Irreversible electroporation, known as IRE, is one of the newest techniques available for treating hard-to-reach soft tissue tumors. The process offers another option for patients who have cancerous tumors that are close to blood vessels, ducts or nerves that may otherwise be damaged using other techniques.

Minimally Invasive Treatment for Inoperable Tumors

IRE is a minimally invasive procedure and requires no surgical incision. The NanoKnife® IRE System, which has been commercially available since 2009, is FDA-approved to treat soft tissue tumors.

Unlike other treatment methods that use thermal ablation -- either heating or freezing -- IRE works by using electrical energy to directly target tumors on the cellular level. IRE destroys tumors using intense bursts of electricity while leaving healthy tissues of the body unharmed.

Electricity is applied through probes inserted through the skin. Ultrasound or CT imaging helps doctors guide the placement of the probes precisely to the site of the tumor. Millisecond electrical pulses are then introduced to open the membranes in the cell walls within the tumor. This irreversible damage causes the cancer cells to die, while nearby nerves, ducts and blood vessels remain unharmed.

IRE is performed under general anesthesia. Because the procedure is considered to be minimally invasive, recovery time may be faster when compared to some other treatments, with some soreness from the needles themselves. There is little scarring because of the way IRE causes the cancer cells to open and die, taking advantage of the body's natural healing ability.

Types of Cancer Treated With IRE

IRE can be used to treat many types of otherwise inoperable soft tissue tumors. Doctors in UMMC's Department of Interventional Radiology are using IRE to treat primary and metastatic liver cancer as well as tissue tumors in the

Who Is a Candidate for IRE Treatment?

IRE is an effective treatment option for tumors near blood vessels or other delicate structures that would otherwise be inoperable or not treatable with other methods.

A consultation with our Vascular and Interventional Radiology experts can help you determine if this treatment is appropriate for you.

Benefits of NanoKnife IRE

  • Doctors can treat otherwise inoperable tumors.
  • Patients receive general anesthesia and experience little or no side effects.
  • The treatment requires only a brief stay in the hospital, usually overnight.
  • The procedure can be repeated if new tumors occur.

What to Expect With IRE

Photo of doctors preparing IRE probesBefore undergoing IRE, you will be scheduled to have imaging studies done, usually an MRI with and without contrast. This allows our experts to evaluate the exact size and location of the tumor and plan the ideal placement of the IRE probes.

You will be asked to return for an appointment approximately two weeks before your IRE procedure to have a pre-procedure work up completed. This visit will include a physical examination and complete medical history. Any necessary lab tests will also be done at this time.

On the day of your procedure, you will come to the Department of Vascular and Interventional Radiology. Doctors will do a CT scan to guide the placement of the four probes that will send the electrical energy to the tumor.

Photo of Doctor Fred Moeslein inserting the IRE probes

The actual IRE procedure lasts only minutes. You will stay in the hospital overnight for observation. In some cases, a repeat MRI may be done. You will be discharged the following day, with a only small bandage placed over the area where the probes were inserted.

Approximately one month after the procedure, you will be asked to return for follow-up imaging to evaluate the treated area.