What Is It?
Thermal ablation is a minimally invasive, image-guided treatment that uses heat or extreme cold to destroy tumor cells, including cancer. Doctors sometimes use ablation to treat benign tumors. This article focuses on ablation for cancerous tumors of the lung, liver, and kidney using cryoablation (sometimes called Cryotherapy), radiofrequency ablation (RFA), and microwave ablation (MWA). Doctors sometimes use cryoablation to treat bone and breast tumors.
While the ablation technique may vary between specific tumor types, the general approach for each procedure is largely the same. Thermal ablation uses ultrasound, computed tomography (CT), or magnetic resonance imaging (MRI) to help guide a needle probe into a cancerous tumor.
RFA and MWA use heat to destroy cancer cells. Cryoablation uses extreme cold to freeze and destroy tumors. Your doctor can discuss the differences between ablation types specific to your diagnosis. For many tumor types, there are no known differences between using heat- and cold-based treatments.
How Is It Treated?
A specially trained interventional radiologist will most often perform image-guided, minimally invasive procedures such as ablation in an interventional radiology suite or occasionally in the operating room. Doctors can perform thermal ablation on an outpatient basis. After some ablation procedures, however, you may need to stay in the hospital overnight for observation.
You will lie on the procedure table. The doctor or nurse may connect you to monitors that track your heart rate, blood pressure, oxygen level, and pulse. A nurse or technologist will insert an intravenous (IV) line into a vein in your hand or arm to administer a sedative.
Your doctor will use medical imaging to precisely locate the tumor. The doctor will sterilize and cover this area with a sterile drape and numb it with a local anesthetic. This may briefly burn or sting before the area becomes numb.
Your doctor may use intravenous conscious sedation and/or general anesthesia in addition to local anesthetic. They will determine the most appropriate type of anesthesia to use during the initial evaluation.
Using imaging-guidance, your doctor will insert the needle through the skin and advance it to the site of the tumor. Once in place, the doctor will activate the probe, freezing or burning the area to kill the tumor cells. A large tumor may require the doctor to do multiple ablations by repositioning the needle electrode or by placing multiple needles into different parts of the tumor. This will help ensure no tumor tissue remains.
Each ablation takes about 10 to 30 minutes, with additional time required if the doctor performs multiple ablations. The entire procedure usually takes one to three hours. At the end of the procedure, the doctor will remove the needle electrode and apply pressure to stop any bleeding. They will cover the opening in the skin with a dressing. No sutures are needed. The doctor or nurse will remove your IV line before you go home.
How Do I Prep For The Procedure?
Tell your doctor about all the medications you take, including herbal supplements. List any allergies, especially to local anesthetic, general anesthesia, or contrast materials. Your doctor may tell you to stop taking aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs) or blood thinners before your procedure.
Prior to your procedure, your doctor may test your blood to check your kidney function and to determine if your blood clots normally.
You should always tell the doctor and technologist if you are pregnant. Doctors will not perform many tests during pregnancy to avoid exposing the fetus to radiation. If an x-ray is necessary, the doctor will take precautions to minimize radiation exposure to the baby. See the Radiation Safety page for more information about pregnancy and x-rays.
Your doctor will likely tell you to fast after midnight before your procedure. They will tell you which medications you may take in the morning. You will need to change into a gown for the procedure.
Some doctors recommend a short, overnight hospital stay after cryoablation of deep tumors. If the procedure uses a large, surgical incision (cryosurgery), you will need a short hospital stay. Doctors can perform percutaneous cryoablation on an outpatient basis, but you may need to stay overnight for observation. Plan to have someone drive you home after your procedure.
What Happens After The Procedure?
Your doctor can control your pain immediately following ablation with medication via IV or by injection. Afterward, oral pain medication can control any mild discomfort. You may feel nauseous. Medication can ease this as well. You should be able to resume your usual activities within one to seven days. You should avoid lifting heavy objects for at least 72 hours.
Only about ten percent of patients will still have pain a week following an ablation. About one-third of patients may develop fever and flu-like symptoms within days after the ablation. This is the body’s reaction to the ablation. It often resolves within 10 days of the procedure.
