Interventional Radiology in Cancer Care Explained

Most people learn two categories quickly. Medical oncologists treat cancer with drugs. Surgical oncologists remove it with an operation.

There is a third. Interventional radiologists treat cancer through a needle or a catheter. Live imaging guides them. When they focus on cancer, they are often called interventional oncologists. The Society of Interventional Radiology calls them a core part of the care team. They can be involved from diagnosis, through treatment, to symptom control.

The defining tool is real-time imaging. That means CT, ultrasound, MRI, or moving X-ray, which is called fluoroscopy. It lets the operator see the target and steer to it. That is why the way in can be a puncture, not a cut.

Many people meet this specialty at the biopsy without knowing it.

A percutaneous biopsy means through the skin. A small needle goes in under anesthesia. Imaging guides it to the tumor. As SIR puts it, patients leave with a small bandage rather than a large cut.

The sample does two jobs. It identifies the cancer type. It also supplies tissue for the molecular tests that decide which targeted treatments might work.

One question is worth asking here. Is enough tissue being taken for molecular tests, and not just for diagnosis? Repeat biopsies happen when the first sample covered one and not the other.

Ablation kills a tumor where it sits. It uses extreme heat, extreme cold, or other energy sent down a probe. SIR lists thermal ablation for kidney cancer, non-small cell lung cancer and breast cancer. It is also common for people who cannot have surgery. The same goes for people who did not respond well to other treatment.

The techniques differ in the physics:

• Cryoablation destroys cells with extreme cold.
• Radiofrequency ablation uses radio waves to make heat. A probe sends out an electrical current. Radio waves heat the tissue around it, and the cells die. The same trick is used to quiet nerves that carry pain.
• Microwave ablation puts a thin antenna into the tumor. A generator sends a wave down it. The wave shakes the water molecules in the tissue. The friction and heat kill the cells.
• Irreversible electroporation is the newest technique. It uses electromagnetic waves rather than heat to destroy cells.
• MRI-guided transurethral ultrasound ablation, or TULSA, treats the prostate. A catheter-like device goes in through the urethra. MRI guides 10 ultrasound elements into place. MR thermometry watches the tissue as it heats above 55 degrees. It also limits heat to the nerves around the gland. The procedure runs 2 to 3 hours, under general or spinal anesthesia. It can be done as an outpatient.

Embolization works through the artery that feeds a tumor. It stops the blood flow, for a time or for good. It can carry treatment in at the same time.

There are three types, and the difference is what travels in with the blockage.

Chemoembolization, also written TACE, is used for liver cancer. A small catheter goes into the femoral artery in the groin. The radial artery at the wrist can be used instead. Live imaging steers it into the liver arteries that feed the tumor. Chemotherapy goes in there, and the blood supply is cut off. The tumor cells then die.

Radioembolization goes by several names. They are selective internal radiation therapy, transarterial radioembolization, and Y-90. The catheter route is the same. What goes in is radioactive beads. They give off radiation over a very short distance. That keeps the dose inside the tumor and spares the rest of the body. The isotope is usually yttrium-90. That is where the Y-90 name comes from.

Bland embolization uses the same method with no drug and no radiation. SIR notes it is often used for neuroendocrine tumors. Those can start in the gut, kidneys, pancreas or lungs.

One point about liver cancer is worth taking into a consultation. SIR says these methods have been shown to downstage liver cancer. That can make a patient a candidate for transplant. It is a specific goal you can ask about. It is not the same as shrinking a tumor for its own sake.

For advanced disease, interventional radiology has a set of tools aimed at symptoms rather than at the cancer itself.

SIR names two. Cement augmentation strengthens bone weakened by tumor. Neurolysis quiets nerves inflamed by cancer.

These sit alongside standard pain care. They do not replace it. If bone pain from cancer is not controlled by medicine, it is fair to ask for an interventional radiology opinion. Our page on palliative care covers how symptom teams work with the rest of your care.

SIR says these treatments are not limited to any one cancer type. It lists the most common ones treated. They are liver cancer, metastatic colorectal cancer, lung cancer, bone cancer, kidney cancer, breast cancer, prostate cancer, neuroendocrine cancer, and childhood cancers.

It adds a needed caution. Some treatments are not right for all cancer types. The decision belongs with your care team.

SIR describes three places for these treatments. They can be first-line therapy. They can be the route when surgery is not an option. And they can be used when other treatments have failed.

The listed advantages are consistent. There is real-time imaging and a small entry point. It is often outpatient. Pain and recovery time are usually less than with surgery or drug treatment.

Questions worth asking:

• Is ablation or embolization an option for my tumor, and at what size or location does that change?
• Would this be instead of surgery, or in addition to it?
• Will I stay overnight, and what is a realistic recovery time?
• Who follows up the imaging afterward, my oncologist or the interventional team?
• Has my case been discussed with an interventional radiologist at a tumor board?

That last question matters. These procedures are often the ones nobody raises. If nobody in the room performs them, nobody proposes them.

Coverage denials are common here. SIR runs a Carrier Advocacy Work Group. It publishes patient appeal letters. Each one uses current clinical evidence to establish medical need for a specific procedure. They are meant for denied prior authorizations, coverage rulings and claim denials.

If a procedure is denied, ask the team whether an appeal letter exists for it. That is a real document, not a general complaint.

For more on the destruction techniques themselves, see our page on tumor ablation. For device care during treatment, see learning to care for a chemo port.

These procedures go in through a puncture, so most of what can go wrong shows up at the entry site or in the days that follow.

• Call 911 or go to an emergency department if the groin or wrist puncture bleeds heavily, or a lump there swells fast. Sudden severe belly pain, a racing pulse, or feeling faint after an embolization also means emergency care now. Go too if a fever comes with shaking chills and you feel confused, are breathing fast, or your skin turns clammy or mottled, which can mean the infection has spread into the blood.
• Call your care team the same day if a fever with shaking chills, without those warning signs, arrives days or weeks after ablation or embolization. Dead tumor tissue can turn into an abscess, and that needs treating rather than waiting out.
• Call your care team within a day or two if the dull ache, nausea, and flatness of post-embolization syndrome is not easing, or is stopping you from drinking.

• Society of Interventional Radiology: cancer
• NCI: radiation therapy for cancer
• StatPearls: hepatic chemoembolization