Embolization

Cancer arises when abnormal cells multiply unusually rapidly and accumulate in masses called tumors. Cancer cells are often invasive: they can overrun and destroy normal body tissues, and they can metastasize—spread from their original site to other parts of the body. Doctors have traditionally treated cancer with surgery, radiation therapy, or chemotherapy to try to stop a tumor’s uncontrolled growth. 

In interventional radiology, an increasingly important form of cancer therapy, specially trained physicians introduce instruments such as needles or catheters (long, thin tubes) equipped with micro-tools into the body through tiny incisions in the skin. Using imaging techniques such as X-ray, ultrasound, CT, or MRI, they guide the instruments to organ systems throughout the body and deliver cancer treatment directly to the tumor. Compared to open surgery, this minimally invasive form of therapy requires less anesthesia, causes less trauma and pain, and patients have shorter hospital stays and recover more quickly. 

What is embolization?

Embolization is an interventional procedure in which we occlude, or block, blood vessels that supply tumors with blood. This approach is especially useful for tumors that are difficult or impossible to remove surgically. Using imaging guidance the interventional radiologist passes a catheter from a small opening in the groin to the tumor, injects a contrast dye to highlight the blood vessels and tumor, and blocks the artery feeding the tumor with synthetic materials called an “embolic agent” (an FDA-approved polyacrylamide microsphere with a gelatin coating). Following embolization the tumor may shrink or grow more slowly, making it possible for doctors to treat the smaller tumor with chemotherapy or surgery.

In some forms of embolization we target chemotherapy or radiation directly at a tumor with minimal side effects:

• During radioembolization, we inject radioactive microspheres to treat both primary and metastatic tumors, mostly applied in the liver.
• During chemoembolization, we inject chemotherapy-laden particles directly to the tumor to enable us to treat the tumor directly with high doses of chemotherapy while minimizing the dose to the rest of the body.

The embolic agent keeps the chemotherapy drug or radioactive microspheres in the tumor and blocking it from traveling to other areas of the body.

How do I get ready for the procedure?

For most forms of embolization you will be given a sedative before the procedure, and should not eat or drink anything for four to eight hours before your exam. Since you will stay in the hospital for one or more days, bring what you need for overnight stays.

What will happen during the procedure?

A physician typically inserts a catheter at a point in the groin to access the femoral artery, although he or she may sometimes use an arm artery. While monitoring the location of the catheter using fluoroscopy, the physician steers the catheter through the arterial system to the tumor. Eventually, the physician delivers cancer treatment through the catheter directly to the tumor. The physician may also use long, thin needles to deliver treatment to cancer tumors.

Are there any risks?

In general, interventional therapy is safe and commonly associated with only minor side effects, including low-grade fever, nausea, and pain. The most serious risk is that an interventional procedure may cause hemorrhage, or bleeding, and, very rarely, death.

After the procedure

After your treatment you will remain in the hospital for one to four days. You can usually resume normal activities soon after leaving the hospital. Patients typically have lower than normal energy levels for about a month after the procedure.