Microwave Ablation
Microwave ablation uses electromagnetic waves to heat and kill small cancerous tumors. These waves are similar to the ones produced by kitchen microwave ovens but are aimed directly at the tumor.
What diseases does microwave ablation treat?
Microwave ablation is used to treat cancers that start in the kidneys, liver and lungs. In these cases, it can be part of the plan to cure the patient.
This therapy is also used to kill tumors from a cancer that started in another part of the body and has spread, or metastasized, to the liver or lungs. These include colorectal cancer, hepatocellular carcinoma (a type of liver cancer), neuroendocrine tumors and pancreatic cancer.
If there are a small number of these tumors, the treatment can help cure the disease. When there are more metastatic tumors, the treatment instead helps slow or stop the cancer’s progress and relieve symptoms.
Who gets microwave ablation?
Microwave ablation is typically offered to patients who are not healthy enough for surgery or whose tumors cannot be removed with surgery due to their size, location or the number of tumors. In some cases, the procedure shrinks the tumor enough to make surgery possible.
What happens during a microwave ablation procedure?
During a microwave ablation procedure, doctors use a live image from an ultrasound or CT scan to guide a needle-like probe to the tumor. The probe then generates microwaves, which heat and kill the cancer cells. The entire procedure takes less than two hours.
Microwave ablation is performed under general anesthesia. Most patients spend one night in the hospital after the procedure. Patients are usually able to walk a few days after the procedure and are fully recovered in two to three weeks.
What are the side effects of microwave ablation?
In general, the side effects of microwave ablation are mild and easy to manage.
Possible side effects include pain at the injection site, bleeding and infection. Some patients experience flu-like symptoms, which can be treated with over-the-counter medications.
Liver tumor patients may also feel pain in the shoulder area. This is caused by a nerve that connects to both the liver and the shoulder.
Kidney cancer patients could experience damage to the system that collects urine and sends it to the bladder. Doctors may use a short-term catheter to prevent this damage or deal with its effects.
Lung cancer patients may develop pneumothorax, or a collapsed lung, caused by air collecting around and putting pressure on the organ. Patients may get a temporary tube in the chest that helps release this air.
In rare cases, the treatment can lead to more serious complications, such as bleeding or the formation of swollen, pus-filled pockets called abscesses.
Microwave ablation at MD Anderson
Choosing where to go for cancer care is one of the most important decisions you can make. At MD Anderson, patients are treated by a team of doctors that usually includes a medical oncologist, surgeon, radiation oncologist and interventional radiologist. They work together to design a personalized treatment plan tailored to each patient.
If the team recommends microwave ablation, you’ll get care from leaders in the field. Our doctors are among the most experienced in the world at microwave ablation treatment. This gives them incredible expertise when designing each treatment. As members of a top-ranked cancer center, they have access to the most advanced technologies, allowing them to deliver the most effective treatment while minimizing side effects.
And at MD Anderson you will be surrounded by the strength of one of the nation's largest and most experienced cancer centers. From support groups to counseling to integrative medicine care, we have all the services needed to treat not just the disease, but the whole person.
How is ablation therapy used to treat cancer?
Ablation therapy is a minimally invasive surgical procedure that kills cancer cells with either very hot or very cold temperatures.
It is used to treat both primary tumors in their original locations and cancers that have spread — or metastasized — to other organs.
To learn more about the risks and benefits of ablation therapy, as well as how it works and which patients might be eligible to receive it, we spoke with Interventional Radiologist Joshua Kuban, M.D.
How many types of ablation therapy are there?
Right now, the only ablation therapy that uses extremely cold temperatures to kill cancer cells is called cryoablation.
There are several types of ablation therapy that use heat energy:
How does ablation therapy work?
With cryoablation, probes are inserted into tumors through tiny holes in the skin. A compressed gas travels through the probes and as it expands, an ice ball forms around each needle, creating a “zone of death.” The frozen tissue is allowed to thaw for a few minutes, then refrozen. The process of repeated freezing and thawing is what destroys the cancer cells.
With ablation therapies that use high heat, thin metal rods called antennae are inserted in or around a tumor, then activated to become really hot. Once they’ve reached the desired temperature, they’re left in place for a few minutes. Then, they’re deactivated and removed.
Do patients need anesthesia to receive ablation therapy?
Some do. But it depends on the location of the cancer and the type of therapy being administered.
If the cancer is easy to target, we might just give someone a sedative and pain medication so they will be very relaxed. But if it’s located deep inside the body, we often use general anesthesia.
What are the benefits of ablation therapy?
The biggest benefit is probably that it’s so minimally invasive. Pain is often minimal, too. Some patients go home the same day as the procedure, and some stay for 12 hours or so. It’s rare that patients have to be admitted to the hospital, though, and most can get back to a desk job within a day or two.
Another benefit of ablation therapy is that it’s not a systemic treatment like chemotherapy, which affects the entire body. So, you won’t see side effects like fatigue or hair loss.
Some recent technological advances have helped us quite a bit, too. Up until five or six years ago, we went in, did the ablation and hoped we got all the cancer. Now, we have advanced 3D targeting and artificial intelligence (AI)-enhanced software that help us to make sure we get the entire tumor during an ablation. That’s significantly improved our success rates and made MD Anderson the leading center in the U.S. for ablation therapy.
Are there any risks with ablation therapy?
As with any surgical procedure, there’s always some risk of infection or bleeding, but those risks are very small. The incision itself is usually about the size of a pen tip, so the risks are much lower with ablation therapy than they would be with traditional open surgery.
Does ablation therapy have any side effects?
The most commonly reported side effect with ablation therapy is pain. But most patients have light to moderate pain that can be easily controlled with either over-the-counter drugs or prescription pain relievers. And some patients don’t experience any pain with ablation therapy.
What types of cancer can be treated with ablation therapy?
Cryoablation therapy is used a lot with lung cancer, as well as any disease that frequently metastasizes to the lungs, such as pancreatic cancer, colorectal cancer, bone cancer, kidney cancer and soft tissue sarcoma. It is also sometimes used to treat nerve pain.
Radio frequency ablation (RFA) was the earliest form of ablation therapy. It’s not used as much anymore, but it’s still used in the kidney, spine, lungs, and sometimes the liver.
Microwave ablation therapy is more powerful than RFA, making treatments faster, but it can also be less forgiving in some tissues. So, we use this method mostly to treat liver cancer and kidney cancer, as well as anything that can spread to the liver, such as colon, breast cancer or neuroendocrine tumors. It can also be used to treat tumors in the lung when they are in certain locations.
Are there any other forms of ablation therapy?
Yes. The methods described above are what we most commonly use, and then we have the next level, which includes approaches for cancers that don’t respond well to any other methods.
- Irreversible electroporation (IRE) uses a change in electrical voltage to kill cancer cells, rather than heat or cold. High voltage electricity creates holes (or pores) in the cancer cells, but if it doesn't last long enough, the cells can repair themselves. With higher voltage and longer times, the damage remains, so the cells leak fluids and die. This is a great option for diseases like bile duct cancer, since IRE kills the cancer cells but leaves the scaffolding around them unchanged.
- High-dose brachy-radio therapy (HDBRT) involves putting a catheter in a tumor and passing a really high dose of radioactive material into the tumor instead of heat energy. It sits there for between 30 seconds and 5 minutes, treating the cancer from the inside out, then is removed. This minimizes damage to any surrounding tissues. It’s used mostly in the liver and for soft tissue tumors.
How would a patient know if they’re eligible for ablation therapy?
There are three main pathways to ablation therapy:
- In-house referrals: Interventional radiologists like me sit on all the same tumor boards as the surgical oncologists and medical oncologists at MD Anderson. These are teams of experts who meet regularly to decide on the best treatment plans for their patients. If we think ablation would be a good option for a particular patient, we’ll speak up and say so.
- Outside providers: Oncologists from other medical systems routinely ask us if we’ll take a look at some of their patients.
- Interventional Oncology Clinic: We work directly with patients and other medical professionals to provide access to cutting-edge therapies and procedures which we offer that other facilities don’t.
What’s the one thing you want people to remember about ablation therapy?
Ablation therapy can be both minimally invasive and maximally effective. But where you go for it really matters.
You want to make sure you’re going to a place that has the right equipment, the right expertise and the right patient volume to give you a good result. That means choosing a facility that does seven or eight of these procedures a day, not just one or two a month.
MD Anderson is so big that our doctors subspecialize in particular areas of ablation therapy. That means better results for our patients. So, that’s what we offer that’s different from everyone else.
Request an appointment at MD Anderson online or call 1-877-632-6789.