Endometrial Cancer: Radiation Therapy

March 21, 2017

Endometrial Cancer: Radiation Therapy 

What is radiation therapy?

Radiation therapy is a treatment for cancer that uses rays of energy. A machine directs the rays of energy to the area of cancer. Radiation therapy is also called radiotherapy. Its goal is to kill or shrink cancer cells.

When radiation therapy may be used

Your doctor may advise radiation therapy if one or more of the below applies to you:

  • You are not able to have surgery.

  • You had surgery for endometrial cancer. Having radiation after surgery can help lower the chances of the cancer coming back. It’s the most common reason to have radiation for endometrial cancer. Radiation after surgery is not started until you've had some time to heal. This is usually about 4 to 6 weeks after surgery.

  • You are having chemotherapy or hormone therapy, and radiation may help ease symptoms such as excess bleeding.

How radiation therapy is done

There are two main ways of radiation therapy:

  • External radiation. The radiation comes from a machine and is pointed at the skin over the tumor.

  • Internal radiation (brachytherapy). This is the most common type of radiation therapy for endometrial cancer. It is usually done after surgery. Radioactive material is placed inside the vagina, near the tumor. This therapy can help lower the risk of the cancer returning with fewer risks than external beam radiation to the whole pelvis.

Which method is 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

Deciding on a radiation treatment plan

You will talk with a radiation oncologist. This is a doctor who specializes in both cancer and radiation. You’ll work with your doctor to decide what your treatment will be and how long it will last. During your visit, ask what you can expect to feel during and after the treatment. 

The goal of radiation therapy

The goal depends on when you get the treatment, for example:

  • Radiation after surgery. The goal is to help make sure that all cancer cells that may not have been removed are killed.

  • Radiation before, during, or after chemotherapy. The goal is to ease symptoms. 

  • Radiation before, during, or after hormone therapy. The goal is to ease symptoms. 

What to expect during external radiation therapy

The treatment is a lot like getting an X-ray. The radiation comes from a large machine. The machine doesn't touch you during the treatment. The treatments don't hurt and they are quick. Radiation is often given once a day, 5 days a week, for about 5 to 6 weeks.

Before you start treatment, imaging scans will be done in the area of your cancer. This is done to measure the exact location of the tumor so the beams of radiation can be focused there. Small marks may be put on your skin to mark the treatment area. This ensures that the radiation reaches only the tumor, and not healthy parts of your body.

On the day of treatment, the process will likely take less than an hour. You are carefully put into the right position. You may see lights from the machine lined up with the marks on your skin. The therapist will leave the room while the machine sends radiation to the cancer. During this time, he or she can see you, hear you, and talk to you. When the machine sends radiation to the cancer, you will need to be very still, but you do not have to hold your breath.

What to expect during brachytherapy

For brachytherapy, a cylinder filled with a radiation source is put into the vagina so that the upper part of the vagina closest to the uterus is treated. This part of the vagina is called the cuff.  This type of radiation may be given in a hospital or in an outpatient radiation clinic. Brachytherapy is given in 2 different ways: 

  • High-dose rate (HDR) brachytherapy. This uses more intense doses of radiation that are put in for less than an hour at a time. There's no need to stay in the hospital, and you can go home after the source is taken out. HDR brachytherapy may be given weekly or daily, most often for about 3 doses total.

  • Low-dose rate (LDR) brachytherapy. This is usually done in the hospital, but it's not often used in the U.S. The radiation source is put in and left in place for about 1 to 4 days. During this time you can’t move very much.

What are common side effects of radiation therapy?

Talk to your doctor about what you might feel like during and after radiation therapy. Side effects often get worse as treatment goes on, but can be treated. They often get better or go away over time after treatment ends. The side effects of radiation therapy include:

  • Skin in the treated area.

  • Lining of the vagina that’s irritated, dry, red, and blistered like sunburn from brachytherapy (the most common side effect of brachytherapy)

  • Hair loss in the area being treated

  • Feeling tired or weak

  • Nausea or diarrhea

  • Bladder irritation

  • Bowel irritation

Side effects depend on the type of radiation therapy used. For example, with brachytherapy the radiation mainly affects the parts of the vagina in contact with the cylinder, so there are fewer side effects. 

Side effects tend to be worse if you're having chemo along with the radiation. Talk to your doctor about what side effects you can expect and what can be done to prevent or ease them. 

When to call your healthcare provider

Ask your doctor what symptoms to watch out for. In some cases, you should call your healthcare team. Your doctor may want you to call if you have signs of infection, such as fever or pain that gets worse.

Long-term side effects

Some long-term side effects of radiation may not show up for many years after you finish treatment. These depend on the dose and type of radiation. These also depend on how many times you had the treatment. Vaginal dryness may become a life-long problem. Ask your doctor what to expect.


March 21, 2017


Meyer, LA., Postoperative Radiation Therapy for Endometrial Cancer: American Society of Clinical Oncology Clinical Practice Guideline Endorsement of the American Society for Radiation Oncology Evidence Based Guidelineds, Journal of Clinical Oncology, 2015, Practice Bulletin Clinical Management Guidelines for Obstetrician Gynecologists Endometrial Cancer, The American College of Obstetricians and Gynecologists

Reviewed By:  

Cunningham, Louise, RN,Stump-Sutliff, Kim, RN, MSN, AOCNS