Interventional Radiology Techniques
Systemic treatments like chemotherapy expose the entire body to cancer drugs, leading to side effects and limiting the dose of drug that can be delivered to the tumor. Several interventional radiology (IR) techniques are available for delivering drugs and other therapies exclusively to the region affected by the cancer. These therapies can be effective options for patients with large liver tumors or extensive liver cancer, provided the patient’s ability to function in normal daily routines, and his or her liver function are both acceptable.
Chemoembolization is a method for delivering chemotherapy directly into a tumor. A catheter is placed in a groin artery and guided into the branch of the hepatic artery that supplies blood to the cancer tissue. In a standard chemoembolization procedure, a potent dose of a chemotherapy drug mixed with oil is infused through the catheter to the tumor.
Embolization particles are then injected into the artery, trapping the drug at the cancer site and blocking tumor blood flow. The tumor receives a very high dose of chemotherapy with minimal systemic side effects for the patient.
Alternative chemoembolization techniques use embolization beads that are themselves loaded with the chemotherapy drug. These drug-eluting beads allow for a slow release of the cancer drug over a long period, which leads may lead to fewer systemic side effects. Patients may undergo chemoembolization multiple times if needed.
Radioembolization procedures deliver radiation directly to liver tumors in the form of microscopic beads impregnated with radioactive Yttrium-90 (a product called TheraSphere®). In an outpatient procedure, a catheter is placed into the femoral artery at the groin and guided to the branch of the hepatic artery that feeds the tumor.
Radioembolization beads are then infused through the catheter into the artery. The spheres become lodged in the small blood vessels that feed the tumor, delivering radiation to the cancer site with minimal effect on surrounding healthy tissues.
Local Therapies can be important for patients who are waiting for a liver transplant. The criteria for transplant are strict, and patients whose tumors grow too large can become ineligible for a transplant operation. For these patients, embolization or ablation can serve as a “bridge therapy” — preventing tumors from progressing while the patient is on the transplant waiting list. For some patients who are just outside transplant criteria, regional therapies are sometimes able to shrink a tumor, thereby making the patient eligible for a transplant procedure.
To learn more about embolization and other regional therapies, visit our Regional Cancer Therapy Program section.
Liver tumors can block bile ducts within the liver. This can lead to pain and other complications. For these patients, interventional radiologists can insert wire mesh stents in ducts to relieve tumor pressure. Relieving blockage can help restore liver function, enabling patients to tolerate chemotherapy.