Surgical removal of liver tumors offers the best chance for a cure. Unfortunately, liver tumors are often inoperable because the tumor may be too large, or has grown into major blood vessels or other vital structures. Sometimes, many small tumors are spread throughout the liver, making surgery too risky or impractical. Historically, chemotherapy drugs have been generally ineffective at curing liver cancer.
In treating cancer patients, interventional radiologists can attack the cancer tumor from inside the body without medicating or affecting other parts of the body by using embolization and radiofrequency heat. In treating cancer patients, interventional radiologists use embolization to cut off the blood supply to the tumor (embolization), deliver radiation to a tumor (radioembolization), or combine this technique with chemotherapy to deliver the cancer drug directly to the tumor (chemoembolization).
Chemoembolization is a minimally invasive treatment for liver cancer that can be used when there is too much tumor to treat with radiofrequency ablation (RFA), when the tumor is in a location that cannot be treated with RFA, or in combination with RFA or other treatments.
Chemoembolization delivers a high dose of cancer-killing drug (chemotherapy) directly to the organ while depriving the tumor of its blood supply by blocking, or embolizing, the arteries feeding the tumor. Using imaging for guidance, the interventional radiologist threads a tiny catheter up the femoral artery in the groin into the blood vessels supplying the liver tumor. The embolic agents keep the chemotherapy drug in the tumor by blocking the flow to other areas of the body. This allows for a higher dose of chemotherapy drug to be used, because less of the drug is able to circulate to the healthy cells in the body. Chemoembolization usually involves a hospital stay of two to four days. Patients typically have lower than normal energy levels for about a month afterwards.
Chemoembolization is a palliative, not a curative, treatment. It can be extremely effective in treating primary liver cancers, especially when combined with other therapies. Chemoembolization has shown promising early results with some types of metastatic tumors. Although the individual materials used in this treatment are FDA approved, the treatment itself is not approved for intra-arterial therapy of liver tumors.
Radioembolization is very similar to chemoembolization but with the use of radioactive microspheres. This therapy is used to treat both primary and metastatic liver tumors.
This treatment incorporates the radioactive isotope Yttrium-90 into the embolic spheres to deliver radiation directly to the tumor. Each sphere is about the size of five red blood cells in width. These beads are injected through a catheter from the groin into the liver artery supplying the tumor. The beads become lodged within the tumor vessels where they exert their local radiation that causes cell death. This technique allows for a higher, local dose of radiation to be used, without subjecting healthy tissue in the body to the radiation. The Yttrium-90 radiates from within and, since it is administered in the hepatic artery, it can be viewed as “internal” radiation.
Radioembolization is a palliative, not a curative, treatment-but patients benefit by extending their lives and improving their quality of life. It is a relatively new therapy that has been effective in treating primary and metastatic liver cancers. It is performed as an outpatient treatment. There are fewer side effects from this treatment compared to standard cancer treatments, with the main one being fatigue for seven to 10 days.
Thermal Ablation Treatments Radiofrequency Ablation
For inoperable liver tumors, radiofrequency ablation (RFA) offers a nonsurgical, localized treatment that kills the tumor cells with heat, while sparing the healthy liver tissue. Thus, this treatment is much easier on the patient than systemic therapy. Radiofrequency energy can be given without affecting the patient’s overall health and most people can resume their usual activities in a few days.
In this procedure, the interventional radiologist guides a small needle through the skin into the tumor. From the tip of the needle, radiofrequency energy (similar to microwaves) is transmitted to the tip of the needle, where it produces heat in the tissues. The dead tumor tissue shrinks and slowly forms a scar. The FDA has approved RFA for the treatment of liver tumors.