What is radiation therapy?

Radiation therapy is a treatment for cancer that uses high-energy X-rays. A machine directs the energy beams to the cancer. Radiation therapy can also be done by putting the source of radiation into or near the cancer.

Radiation therapy is also called radiotherapy. Its goal is to kill or shrink cancer cells.

Why might I need radiation therapy?

Your healthcare provider may advise radiation therapy for you in any of these cases: 

• As the main treatment instead of surgery. If you can't have surgery because of other health problems, you may have only radiation.

• To try to shrink the tumor before surgery. Radiation before surgery may help shrink the tumor so it's easier to remove. Getting radiation before surgery is called neoadjuvant therapy. It might also be called preoperative radiation.

• After surgery. Radiation might be used to help kill any cancer cells left after surgery. This can help lower the chance that the cancer comes back in your pelvis or elsewhere. Getting radiation after surgery is called adjuvant therapy. It might also be called postoperative radiation therapy.

• To help ease problems caused by the tumor. If the tumor is big, radiation can be used to shrink it. This may help ease symptoms like pain caused by the tumor pressing on nerves. This is called palliative care. It's not intended to cure the cancer. It's used to treat symptoms caused by the cancer.

How radiation therapy is done

There are two main types of radiation therapy used for uterine sarcoma: 

• External radiation. The radiation comes from a large machine and is pointed at the skin over the tumor. The treatment is a lot like getting an X-ray. The machine doesn't touch you during the treatment. It will move around you and send out beams of radiation from many angles. The treatments don't hurt and they're quick. 

• Internal radiation (brachytherapy). Radioactive material is put into or near the tumor. The radiation source may be put inside flexible tubes called catheters, or in metal rods that are put into the vagina. The radiation only travels a very short distance to kill nearby cancer cells. The radioactive material might be left in anywhere from a few minutes up to a few days.

You may be treated with one or both types of radiation therapy. Radiation therapy is often used along with other cancer treatments, like surgery or chemotherapy. 

The type of treatment used depends on:

• How much the cancer has spread (stage)

• How fast the cancer is growing (grade)

• If it was found in nearby lymph nodes

• The type of sarcoma

Deciding on a radiation treatment plan

You will talk with a radiation oncologist and treatment team. A radiation oncologist specializes in both cancer and radiation. You’ll work with your team to decide what your treatment will be and how long it will last. Be sure to ask how you can expect to feel during and after treatment. 

Before external radiation therapy

If you’re getting external radiation therapy, you’ll have an appointment before treatment starts to learn exactly where in your body the radiation beams need to go. This is a process called simulation. This appointment may take up to 2 hours. Here's what you can expect to happen during the simulation process: 

• You'll lie still on a table while a radiation therapist uses a machine (often a CT or MRI scanner) to find where the cancer is. The scans are used to clearly outline the size and shape of the tumor. The radiation beams are controlled and formed to fit this shape and focus on the tumor. This helps limit damage to nearby healthy tissue.

• A treatment field, also called your treatment port, is defined by your healthcare provider. This field is the exact part of your body where the radiation will be aimed. You may have more than one treatment field if you have cancer in more than one place.

• The therapist will mark your skin with tiny dots of colored semipermanent ink or tattoos. This helps the therapist aim the radiation at the same place each time and limit damage to nearby healthy tissues.

• Body molds or casts may be made to hold you in the best position. They also help keep you from moving during the treatments.

What to expect during external radiation therapy 

You can get external radiation as an outpatient at a hospital or clinic. That means you don't need to stay at the hospital overnight. External beam radiation is given in small daily doses that eventually add up to the total dose. This is called fractionation. You'll be given a treatment schedule. Treatment is usually done 5 days a week for 3 to 7 weeks. Spreading out the radiation dose helps protect your healthy tissues.

On the days you get radiation, you’ll lie on a table while the machine is placed over you. You may have to wear a hospital gown. Treatment is a lot like getting an X-ray, but it lasts longer. The whole process lasts about 15 to 30 minutes. But only about 1 to 5 minutes are spent getting the radiation. A radiation therapist may use special shields to cover other parts of your body to protect it from the radiation. Or the machine itself may have built-in shields to protect you.

The therapist will line up lights on the machine with the dots that were marked during simulation. This helps to make sure that the radiation is going to the right place.

The therapist will leave the room to turn on and run the machine. You’ll be able to hear and talk with the therapist over an intercom, and the therapist can see you the whole time. You can’t feel radiation. It doesn't hurt. You may hear whirring or clicking noises from the machine. It may move around you, but it will not touch you. You will not be radioactive afterward.

What to expect during internal radiation (brachytherapy)

Internal radiation may be given as an outpatient treatment or in the hospital. The radiation only travels a short distance from the source. It travels into the vagina so it's very close to the tumor. Sometimes more than one brachytherapy treatment is needed.

There are two ways this type of radiation is done:  

Low-dose-rate brachytherapy

This treatment is done while you stay in the hospital. It's rarely used anymore. The radiation source is put into your vagina and stays in for 1 to 4 days. During this time, you will stay in a special room that protects others from the radiation. You may have to limit your contact with others. You won't be able to move very much and may have to stay in bed while the radiation is in place.

High-dose-rate brachytherapy

This is given as an outpatient procedure. This means you don’t need to stay in the hospital. A hollow tube or rod is put in your vagina, like a large tampon. A small machine attached to plastic catheters sends the radiation into the tube in your vagina. You have to be still during this time. Your healthcare provider will talk with you about how long the radiation stays in. After that time, the machine takes the radiation source out and the tube is removed. You are not radioactive after the procedure. The entire process usually takes a few hours. It may be done 2 or 3 times.

What happens after radiation therapy? 

After you finish getting your radiation therapy, your oncologist and other healthcare providers will closely watch you to see how your body responds to the treatment. Lab tests and scans will be done on a regular basis. Make sure you tell your healthcare providers about any problems or symptoms you have. Also be sure to go to all your follow-up appointments.

Common side effects of radiation therapy

Radiation can damage normal cells as well as cancer cells. This can lead to side effects. Side effects cause problems in the treated part of your body. They often get worse as treatment goes on but can be treated and controlled. In most cases, they will go away or get better over time after treatments end. These are called short-term side effects. Still, if you have side effects, talk with your healthcare provider about how to deal with them.

The side effects you have depend on: 

• Whether you get internal or external radiation, or both

• How much radiation you get (the dose)

• Whether you get chemo along with radiation

• Which normal tissues are affected by the radiation, such as your skin, bladder, rectum, vagina, lymph system, or blood cells

Some side effects start during treatment. Others may happen weeks or months after treatment.

Short-term side effects of radiation therapy for uterine sarcoma may include: 

• Extreme tiredness

• Redness, itching, or peeling on the skin in the treatment area, including the vagina

• Nausea

• Bloating

• Loss of hair, especially pubic hair, which may not come back

• Genital and vaginal soreness

• Diarrhea or intestinal cramping from radiation irritation to the intestines

• Feeling the need to urinate often or a burning feeling when you urinate from radiation irritation to the bladder

• Infections from low white blood cell levels

• Easy bruising or bleeding from low blood platelet levels

Long-term side effects are also possible and can include:

• Bladder problems

• Scar tissue in the vagina and dryness called vaginal stenosis that can make vaginal sex painful

• Ovary damage that can lead to early menopause (change of life) and make you infertile (unable to have children) if you didn't already have surgery

• Lymph node damage that causes genital and leg swelling (lymphedema)

• Hip and pelvic bone weakness that can lead to bone breaks

• Bowel problems. These may include long-lasting (chronic) diarrhea or even blockages.

Ask your healthcare provider which side effects you are most likely to have. Be sure you know which short- and long-term side effects to watch for and tell your healthcare team about. Most side effects can be treated. And there may be things you can do to help prevent them. For instance, vaginal dilators can help stretch and move the walls of the vagina to keep scar tissue from forming.

When to call your healthcare provider

Ask your healthcare provider what problems you should watch for and what to do if they become serious. In some cases, you might need to call your healthcare team. For instance, your healthcare provider will want you to call if you have signs of infection, such as fever, or pain that gets worse. Make sure you know what number to call with questions or problems. Is there a different number for evenings, holidays, 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.