Radiation therapy uses high energy x-rays or particles to kill cancer cells.
External beam radiation
One way to give radiation is to aim x-rays at the cancer from outside the body. This is called external beam radiation therapy (EBRT). Treatment is much like getting a regular x-ray, but the radiation dose is stronger. Each treatment lasts only a few minutes, although the setup time – getting you into place for treatment – usually takes longer. The procedure itself is painless, but does result in some side effects.
When radiation is used as the main treatment for cervical cancer, EBRT is usually combined with chemotherapy (called concurrent chemoradiation). Often, this is a low dose of a drug called cisplatin, but other chemotherapy drugs can be used as well. The radiation treatments are given 5 days a week for 6 to 7 weeks to complete.
EBRT can also be used by itself to treat areas of cancer spread or as the main treatment of cervical cancer in patients who can’t tolerate chemoradiation.
Common side effects of external beam radiation therapy include:
- Fatigue (tiredness)
- Upset stomach
- Diarrhea or loose stools (if radiation is given to the pelvis or abdomen)
- Nausea and vomiting
- Skin changes
Skin changes are common. As the radiation passes through the skin to the cancer, it can damage the skin cells. This can cause irritation ranging from mild, temporary redness to peeling. The skin may release fluid, which can lead to infection, so the area exposed to radiation must be carefully cleaned and protected.
Radiation to the pelvis can also irritate the bladder (radiation cystitis), causing discomfort and an urge to urinate often.
Radiation can affect the vulva and vagina, making them sensitive and sore, and sometimes causing a discharge.
Pelvic radiation can also affect the ovaries, leading to menstrual changes and even early menopause
Radiation can also lead to low blood counts, which can cause:
- Anemia (low red blood cells), which can cause you to feel tired
- Leukopenia (low white blood cells), which increases the risks of serious infection
These side effects improve in the weeks after radiation is stopped.
The blood counts tend to be lower when chemotherapy is given with radiation and fatigue and nausea also tend to be worse.
Another type of radiation therapy is called brachytherapy, or internal radiation therapy. This involves placing a source of radiation in or near the cancer. For the type of brachytherapy that is used most often to treat cervical cancer, intracavitary brachytherapy, the radiation source is placed in a device that is in the vagina (and sometimes the cervix). This is often used in addition to EBRT as a part of the main treatment for cervical cancer.
To treat cervical cancer in women who have had a hysterectomy, the radioactive material is placed in a cylinder in the vagina.
To treat a woman who still has a uterus, the radioactive material can be placed in a small metal tube called a tandem that goes in the uterus, along with small round metal holders called ovoids placed near the cervix. This is sometimes called tandem and ovoid treatment. Another option is called tandem and ring. For this, a round holder (like a disc) is placed close to the uterus. Which one is used depends on what type of brachytherapy is planned.
Low-dose rate brachytherapy is completed in just a few days. During that time, the patient remains in bed the hospital with instruments holding the radioactive material in place.
High-dose rate brachytherapy is done as an outpatient over several treatments (often at least a week apart). For each high-dose treatment, the radioactive material is inserted for a few minutes and then removed. The advantage of high-dose rate treatment is that you do not have to stay still for long periods of time.
In brachytherapy, radiation only travels a short distance, so the main effects of the radiation are on the cervix and the walls of the vagina. The most common side effect is irritation of the vagina. It may become red and sore and there may be a discharge. The vulva may become irritated as well. Brachytherapy can also cause many of the same side effects as external beam radiation, such as fatigue, diarrhea, nausea, irritation of the bladder, and low blood counts. Often brachytherapy is given right after external beam radiation (before the side effects can go away), so it can be hard to know which type of treatment is causing the side effect.
Long-term side effects of radiation therapy
Both external beam radiation to the pelvis and brachytherapy can cause scar tissue to form in the vagina. The scar tissue can make the vagina more narrow (called vaginal stenosis), less able to stretch, or even shorter, which can make vaginal intercourse painful. A woman can help prevent this problem by stretching the walls of her vagina several times a week. Although this can be done by having sexual intercourse 3 to 4 times a week, most women find that hard to do during (or in the weeks after) treatment. The other way to stretch out the walls of the vagina is by using a vaginal dilator (a plastic or rubber tube used to stretch out the vagina). A woman getting radiation does not have to start using the dilator during the weeks that radiation is being given, but she should start by 2 to 4 weeks after treatment ends. Because it can take a long time to see the effects of radiation and because the radiation effects are long lasting, it is recommended that the dilator be used indefinitely.
Vaginal dryness and painful intercourse can be long-term side effects from radiation (both brachytherapy and external beam radiation). Vaginal (local) estrogens may help with vaginal dryness and changes to the vaginal lining, especially if radiation to the pelvis damaged the ovaries, causing early menopause. More information about managing the sexual side effects of cervical cancer treatment can be found in our document Sexuality for the Woman with Cancer.
Radiation to the pelvis can also weaken the bones, leading to fractures. Hip fractures are the most common, and might occur 2 to 4 years after radiation. Bone density studies are recommended.
If pelvic lymph nodes are treated with radiation, it can lead to fluid drainage problems in the leg. This can cause severe swelling in the leg, a condition called lymphedema. More information about lymphedema can be found in our document, Understanding Lymphedema – For Cancers Other Than Breast Cancer.
If you are having side effects from radiation treatment, discuss them with your cancer care team.
It is important to know that smoking increases the side effects from radiation and can make treatment less effective. If you smoke, you should stop.
For more information, please see the Radiation Therapy section of our website or our document Understanding Radiation Therapy: A Guide for Patients and Families.
Last Revised: 01/29/2016