Liver Cancer: Radiation Therapy
What is radiation therapy?
Radiation therapy uses high-energy radiation from X-rays or particles to kill cancer cells.
When might radiation therapy be used?
Radiation therapy is sometimes used to shrink tumors in the liver, but it is not a major part of the treatment for most liver cancers. This is because other treatments tend to work better. Still, radiation might be a choice if the cancer can't be removed by surgery for some reason. This might be because of the size or location of the tumor. Or it might be because you have other health problems.
To plan your entire treatment strategy, you will talk with a team of cancer specialists. This might include a surgeon, radiation oncologist, and medical oncologist.
How is radiation therapy given?
You can get radiation therapy for liver cancer in 2 main ways.
One way to get radiation is from a machine outside your body. The machine gives off invisible beams (X-rays) or other types of radiation. One problem with this treatment is that even normal liver cells are very sensitive to radiation. This can cause side effects. Newer forms of radiation therapy focus the radiation more precisely at the tumor. Examples are 3-D conformal radiation therapy (3DCRT) and stereotactic body radiation therapy (SBRT). These can lower the risk for side effects.
A doctor who specializes in giving external radiation to treat cancer is called a radiation oncologist. This doctor works with you to figure out the kind of radiation you need. This doctor also figures out the dose and how long you need the therapy.
You can usually get external radiation therapy as an outpatient in a hospital or a clinic. Most types of external radiation are given 5 days a week for several weeks. Because SBRT focuses higher doses of radiation at the tumor, it is typically given over one to a few days.
For this technique, a doctor called an interventional radiologist puts a long, thin, flexible tube (catheter) into an artery in your groin. He or she watches it on X-rays as it's threaded it up into the artery in your liver (hepatic artery). Then the doctor injects tiny radioactive beads into the artery. The beads go into the liver near tumors and get stuck in the small arteries there. The beads give off small amounts of radiation that travel only a short distance.
Preparing for external radiation
Before your first radiation treatment, you will have a session (simulation) to find out exactly where on your body the radiation beam needs to be aimed. This session may take up to 2 hours. You may have imaging tests such as CT scans, MRI scans, or ultrasound to help doctors know where your tumor is to better aim the radiation. Then you’ll lie still on a table while a radiation therapist uses a machine to define your treatment field. The field is the exact area on your body where the radiation will be aimed. Sometimes it’s called your port. The therapist may mark your skin with tiny dots of semi-permanent ink. This is done so that the radiation will be aimed at the exact same place each time. Also at this session, you may have body molds made to help keep you from moving during the treatment.
On the days you get radiation
On the days you get radiation treatment, you’ll lie on a table while the machine is placed over you. You may have to wear a hospital gown. The treatment is much like getting an X-ray, but it takes longer. It typically takes about 15 to 30 minutes to complete. You should plan on being there for about an hour.
At the start of the treatment session, a radiation therapist may place blocks or special shields on you. This will protect parts of your body that don’t need to be exposed to radiation. The therapist then lines up the machine so that radiation is directed to the spot that was marked during the simulation. When you are ready, the therapist leaves the room and turns the machine on. You may hear whirring or clicking noises, similar to the sounds of a vacuum cleaner, while the machine moves around you and the radiation is given. During the session, you will be able to talk to the therapist over an intercom. You can’t feel radiation and the machine will not touch you, so the process will not hurt. Also you will not be radioactive afterward.
What to expect after radiation therapy
Because radiation affects normal cells as well as cancer cells, you may have some side effects from this treatment. Some people have few or no side effects. If you do have them, your doctor may change the dose of your radiation or how often you get the treatments. Or the doctor may stop treatment until the side effects are cleared up. Be sure to tell your doctor about the side effects you have.
Side effect of radiation therapy
These are some of the more common short-term side effects:
Skin irritation, redness, blistering, or other changes in areas that get radiation
The liver is very sensitive to radiation. If a large part of your liver is treated, you may get radiation hepatitis. This can lead to yellowing of your skin (jaundice) and other problems.
Some of these side effects can be controlled with medicine, and some may be helped with diet. Talk with your doctor or nurse about how to deal with them and how to know when they become serious. Usually these side effects go away a few weeks after you stop getting treatment.
June 27, 2018
Nonsurgical therapies for localized hepatocellular carcinoma: Transarterial embolization, radiotherapy, and radioembolization. UpToDate.
LoCicero, Richard, MD