Microwave and Radiofrequency Ablation

September 3, 2024

This page was reviewed under our medical and editorial policy by Jonathan Kessler, M.D., associate clinical professor, division of interventional radiology, Department of Diagnostic Radiology, City of Hope^® Cancer Center Duarte

Microwave ablation (MWA) is a procedure that uses high temperature microwaves to destroy abnormal tissue. Radiofrequency ablation (RFA) also heats and destroys tissue, but by using radio waves.

One of these interventional radiology procedures may be incorporated into a patient’s cancer treatment plan to shrink tumors.

They are typically performed by an expert called an interventional radiologist.

Microwave Ablation

During microwave ablation, a machine called an ablation generator is used to create energy from electromagnetic waves. This energy heats up and destroys abnormal tissue. MWA may be used to treat tumors of the lung, liver, pancreas, kidney and bones.

Microwave Ablation Procedure

Microwave ablation is typically an outpatient procedure where patients are discharged from the hospital within 24 hours. 

Patients will receive sedation or anesthesia as well as a local anesthetic prior to their ablation so they feel no pain or discomfort during the procedure. 

During the ablation, doctors advanced imaging modalities such as computed tomography (CT) or ultrasound to guide the treatment probe through the skin to its target tumor location. Electrical current runs through it, heating the tumor tissue to greater than 300 degrees Fahrenheit, causing it to die. 

The exact length of the treatment time depends on the type, location and number of tumors being treated.

Microwave Ablation Side Effects

As with any medical procedure, side effects are possible. Side effects typically last three to seven days and vary depending on the location and amount of treatment that is needed. Typical side effects associated with microwave ablation may include:

• Pain in the treated area
• Low-grade fever
• Malaise or fatigue

What Is Radiofrequency Ablation?

Radiofrequency ablation employs high-energy radio waves to treat some tumors of the liver, bone, kidney, lung, and thyroid. It is typically used to treat locally advanced tumors that are less than 3 centimeters in diameter.

Radiofrequency Ablation Procedure

Like microwave ablation, radiofrequency ablation is often an outpatient procedure. Sedation or anesthesia are typically given, so a patient should arrange for someone to drive them home afterward. A member of the care team will give specific instructions regarding stopping any medication, as well as eating or drinking beforehand.

During the procedure, doctors use ultrasound and CT imaging to guide placement of the probe, which delivers a high-frequency alternating current to the tumor. This current heats the tumor to over 200 degrees Fahrenheit, causing the tissue to die. The procedure’s duration depends on how many tumors are being treated.

Radiofrequency Ablation Side Effects

Side effects of radiofrequency ablation are similar to those of microwave ablation and may include:

• Pain in the treated area
• Low-grade fever
• Malaise or fatigue
• Infection

Any severe side effects should be reported to the patient’s care team right away.