What are Liver Cancer Treatment Options?
The best treatment for primary liver cancer is to remove it surgically. Unfortunately, that is seldom possible; in fact, fewer than 10% of patients are suitable for surgery. This may be because the liver function is too poor due to cirrhosis for the patient to go through surgery safely or because there are several tumors that are too widespread to remove them all. For example, cirrhosis makes it difficult for patients to get safely through almost any type of operation, and when cutting the liver is involved, as many as half might die due to bleeding, infection, or liver failure. Frequently, there are other tiny deposits of cancer elsewhere in the liver that are not visible at surgery or on scans, but will eventually grow back after successful surgery. Despite these issues, however, surgical techniques have steadily improved over the past 20 years, making it ever safer and more effective for many people to undergo an operation. Currently, more than half of patients will survive more than five years after removal of their cancer.
If there is no evidence of the spread of a primary liver cancer beyond the liver, then liver transplantation can be considered. Liver transplantation involves removing the entire liver surgically and replacing it with a healthy liver from a donor. In order for the new liver to be accepted by the body, the immune system has to be severely suppressed and held back from attacking the new liver. Recent advances in transplant techniques and immune medications have made transplantation the first choice for patients with cirrhosis and small tumors. These are people who would not have been able to have surgery due to their liver disease but now have a greater than 70% chance of living more than five years. Unfortunately, there are not enough donor livers for everyone, and the waiting time on the transplant list can be over a year. The rise in successful experience with live donors and partial-liver transplantation increases the chance that someone can go through with this difficult but potentially life-saving operation.
If surgery is not possible, there are other treatments that can attack the tumor specifically with liver-directed therapy. The tumor may be injected with a toxic material such as pure alcohol or chemotherapy in order to kill it. It can be frozen and killed with supercold liquid nitrogen (cryotherapy). Microwaves, radio waves, or laser can be directed at the tumor to kill it using heat energy. This is the principle behind radiofrequency ablation, in which a metal probe is inserted into the tumor under ultrasound or CT scan guidance. Thermal (heat) energy is created by radio waves coming from the tip of the probe, and this damages the surrounding cells, killing the tumor. These local techniques are limited to people with only one or two small tumors, in general.
Chemotherapy drugs can be given directly into the blood vessel that feeds the liver and the tumors; in addition, the blood flow to the tumor can be cut off by injecting tiny particles that block the feeding arteries. This procedure, called chemoembolization, attempts to kill the tumor in two ways: by bathing the tumor directly in a very high concentration of chemotherapy and by starving it of its blood supply. Although effective, chemoembolization requires a hospital admission, and can cause pain, fever, nausea, and liver damage.
A similar technique, using microscopic radioactive particles instead of chemotherapy injected into the blood vessels, is called radioembolization or selective internal radiation therapy (SIRT). This uses radioactive yttrium attached to glass microspheres and may be as effective as chemoembolization for small and multiple tumors.
Radiation therapy uses high-dose energy like X-rays aimed at a small part of the body and can frequently destroy cancer cells. The normal cells of the liver, though, may be more sensitive to the radiation than the tumor is, so standard radiation is seldom used. However, there are new specially focused techniques called conformal or stereotactic radiation that may be useful in certain cases.
Chemotherapy refers to drugs that are usually given by pill or by vein. They are designed to work throughout the entire body, not just the liver, so tumors outside the liver will be treated as well. However, chemotherapy does not always work well for primary liver cancers. Since the liver functions by removing poisons from the body, it can treat chemotherapy drugs as just another toxic chemical it needs to resist. Many standard drugs have been tested, and there are certain combinations that can be helpful to shrink the cancer. Recently, agents that directly attack the microscopic blood vessels in the tumor, called antiangiogenic drugs, have proven to be very helpful. Sorafenib, the first drug to be approved specifically for hepatoma, was introduced in 2007. Sorafenib is a pill that slows the growth of the cancer and helps keep many patients alive longer.