Radiation therapy uses high-energy rays (or particles) to destroy cancer cells. Radiation therapy is the preferred method of treating most cancers of the vagina.

There are several ways to deliver radiation therapy. The most common way is to carefully focus a radiation beam from a machine outside the body. This is known as external beam radiation. External beam radiation therapy usually involves having treatments 5 days a week for a period of 6 weeks or so.

The main drawback of this method is that the radiation can destroy nearby healthy tissue along with the cancerous cells. Some people have a skin reaction that is like a sunburn on the outside of their skin. This slowly fades away. Other possible side effects include fatigue, nausea, or diarrhea. To reduce the risk of side effects, doctors carefully figure out the exact dose you need and aim the beam as accurately as they can to hit the cancer.

In addition to these side effects, higher doses of radiation used in treating more advanced cancers may also cause severe irritation of the intestines and rectum, urethral stricture (narrowing of the tube that carries urine out of the bladder), perforations (holes or tears) of the intestines, and fistulas (abnormal connections) between the vagina and the bladder, rectum, or uterus.

Another method of delivering radiation, called brachytherapy, is to place radioactive material inside the vagina. For low-dose brachytherapy (internal radiation therapy) the radioactive material can be placed inside a cylindrical container that is placed in the vagina for a day or two. This method of brachytherapy is called intracavitary radiation. Although gauze packing helps hold the cylinder in place, you have to remain in bed for the course of the treatment.

A second type of brachytherapy, called interstitial radiation, uses radioactive material inside needles that are placed directly into the cancer.

High dose-rate brachytherapy (internal radiation) is given in an outpatient setting. Three or four treatments are given 1 or 2 weeks apart. The treatments are often combined with external beam radiation therapy.

The side effects of intracavitary or interstitial radiation therapy depend on the dose of radiation and whether external beam radiation is also given. The radiation may cause vaginal stenosis (shrinkage and narrowing of the vagina), damage to the normal tissue of the vagina, irritation of the intestines, and diarrhea.

The scarring that normally occurs after radiation could shorten or narrow the vagina so much that a woman may not have intercourse. She can often keep tight scar tissue from forming, however, by stretching the walls of her vagina a few times a week. There are several methods of accomplishing this goal. One option is use of a vaginal dilator.

A dilator is a plastic or rubber tube used to stretch out the vagina. It feels much like putting in a large tampon for a few minutes. If a woman is sexually active, she may choose to engage in sexual intercourse at least 3 to 4 times a week. Even if a woman is not interested in staying sexually active, keeping her vagina normal in size allows comfortable gynecologic exams. This is an important part of follow-up after treatment. Vaginal estrogens may also be used to improve dryness, painful intercourse and help maintain the size of the vagina. Last Revised: 07/21/2006