Kaposi Sarcoma: Radiation Therapy
What is radiation therapy?
Radiation therapy uses high-energy beams of X-rays or particles to kill cancer cells.
When might radiation therapy be used?
Radiation therapy can be used to treat Kaposi sarcoma (KS) lesions near the surface of the body, like on the skin or in the mouth. This is a type of local therapy, meaning it only treats the cancer that it's aimed at. It doesn’t treat the whole body.
Radiation therapy is most often used to treat lesions on the face. It can also be used to treat lesions that are causing symptoms (like pain or swelling), but that are too big to be treated with other types of local therapy.
You will meet with a team of cancer specialists to plan your radiation treatments. This team will include a doctor who specializes in radiation therapy, called a radiation oncologist, and other types of doctors, too.
What happens during radiation therapy?
The most common way to get radiation therapy for KS is from a large machine that emits a beam of radiation that's focused on the cancer. This is called external radiation. The 2 main types of external radiation can be used to treat KS lesions are:
Electron-beam radiation therapy. This is typically used for lesions on the skin. This type of radiation doesn't penetrate deep through the skin and into the tissues below it, which limits the side effects it causes.
Photon-beam radiation therapy. This tends to be used for lesions in the mouth or throat. This type of radiation can penetrate deeper into the body.
Your radiation oncologist will work with you to figure out the kind of radiation you need. This doctor also determines the dose and how long you need treatment.
You get radiation therapy as an outpatient in a hospital or a clinic. Outpatient means you go to get treatment each day. The typical treatment for KS is to get radiation once a week for several weeks.
Before your first treatment, you might have a session to determine exactly where on your body the radiation beam needs to be directed. The process is called simulation.
On the days you get radiation treatment, you’ll lie on a table while the machine moves over and around you. It doesn't touch you. You may have to wear a hospital gown. The experience is a lot like getting an X-ray, only longer. It takes about 15 to 30 minutes to complete. But 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 to 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 at the right spot. When you're ready, the therapist leaves the room and starts the machine. You may hear whirring or clicking noises, like the sounds of a vacuum cleaner, while the radiation is given. During the session, you'll be able to talk to and be heard by the therapist through an intercom. You can’t feel radiation, and treatment doesn't hurt. You won't be radioactive afterward.
What to expect after radiation therapy
Radiation affects normal cells as well as cancer cells. Because of this, you may have some side effects from this treatment. But these are usually limited to the area being treated. Some people have few or no side effects. But if you do have them, your doctor may change the dose of your radiation or the frequency of treatments. Or the doctor may stop treatment until the side effects are gone. Be sure you tell your doctor about any side effects you have. It's important to deal with them right away so they don't get worse.
Side effects might include:
Sometimes, treated KS lesions can become open sores, which might be painful. This is especially true for sores in the mouth or throat.
Usually side effects go away over time after you stop getting treatment.
Working with your healthcare provider
If you have any side effects, talk with your healthcare team about how to deal with them and how to know when they become serious. Make sure you know what number to call with problems or questions. Is there a different number for evenings and weekends?
It may be helpful to keep a diary of your side effects. A written list will make it easier to remember your questions when you go to appointments. It will also make it easier for you to work with your healthcare team to make a plan to manage side effects.