When Is Internal Radiation Therapy Used?
- Your doctor may decide that very intense radiation given to a small area of your body is the best way to treat your cancer. Internal radiation therapy places the source of the high-energy rays as close as possible to the cancer cells so that fewer normal cells are exposed to radiation. By using internal radiation therapy, the doctor can give a higher total dose of radiation in a shorter time than is possible with external treatment. Instead of using a large radiation machine, the radioactive material is placed directly into (or as close as possible to) the affected area. Some of the radioactive substances used for internal radiation treatment include radium, cesium, iridium, iodine, phosphorus, and palladium.
Internal radiation therapy often is used for cancers of the head and neck, breast, uterus, thyroid, cervix, and prostate. Your doctor may recommend a combination of internal and external radiation therapy.
Implant radiation as used in this booklet means internal radiation treatment. You also may hear the terms interstitial radiation, intracavitary radiation, or brachytherapy; each is a form of internal radiation therapy. Some people use the term "brachytherapy" whenever they are talking about any form of internal radiation therapy.
When interstitial radiation is given, the radiation source is placed right in the affected tissue, usually in small tubes or containers. These implants may be temporary or permanent. When intracavitary radiation is used, a container of radioactive material is placed in a cavity of the body such as the uterus. In brachytherapy, the radioactive source, sealed in a small container, is placed on the surface of the body near the tumor or a short distance from the affected area. The radioactive source also may be delivered to the tumor through tubes; this is called remote brachytherapy. Internal radiation also may be given by injecting a solution of radioactive substance into the bloodstream or a body cavity. When the substance is injected, it is not sealed in a container and may be called unsealed internal radiation therapy.
How Is the Implant Placed in the Body?
- For most types of implants, you will need to be in the hospital and have general or local anesthesia while the doctor places the container for the radioactive material in your body. In many hospitals, the radioactive material is placed in the container after you return to your room so that others are not exposed to radiation.
To get the radiation as close as possible to the cancer, doctors may use implants of radioactive material sealed in wires, seeds, capsules, or needles. The type of implant and the method of placing it depend on the size and location of the cancer. Implants may be put right into the tumor, in special applicators inside a body cavity, on the surface of a tumor, or in the area from which the tumor has been taken.
Does the Implant Spread Radiation to Others?
- The radioactive substance in your implant may transmit rays outside your body. While you're receiving implant therapy, the hospital may require you to stay in a private room. Although the nurses and other people caring for you will not be able to spend a long time in your room, they will give you all of the care you need. You should call for a nurse when you need one, but keep in mind that the nurse will work quickly and speak to you from the doorway more often than from your bedside. In most cases, your urine and stool will contain no radioactivity. However, either one may contain some radioactive material if you have unsealed internal radiation therapy.
There also will be limits on visitors while your implant is in place. Most hospitals do not let children younger than 18 or pregnant women visit patients who have an implant. Visitors should sit at least 6 feet from your bed and stay for only a short time each day (10 to 30 minutes). Have visitors ask your nurse for specific instructions before they enter your room.
Are There Any Side Effects?
- You are not likely to have severe pain or feel ill during implant therapy. However, if an applicator is holding your implant in place, it may be somewhat uncomfortable. If you need it, the doctor will order medicine to help you relax or to relieve pain. Some patients feel drowsy, weak, or nauseated after having the anesthesia to place the implant, but these effects do not last long.
Be sure to tell the nurse if you have any side effects such as burning, sweating, or other unusual symptoms. In the section of this booklet called "Managing Side Effects," you will find tips on skin care and what you can do about problems that might occur after implant therapy.
How Long Does the Implant Stay in Place?
- The total amount of time that an implant is left in place depends on the dose (amount) of radioactivity with which the patient is treated. The implant may be low dose rate and left in place for several days, or high dose rate and removed after a few minutes. Generally, low dose rate implants are left in place from 1 to 7 days. Your treatment schedule will depend on the type of cancer, where it is, your general health, and other cancer treatments you have had. Depending on where the implant is placed, you may have to stay in bed and lie fairly still to keep the implant from shifting.
For some cancer sites, the implant may be left in place permanently. If your implant is permanent, you may need to stay in your room away from other people in the hospital for a few days while the radiation is most active. The implant will lose energy each day, so by the time you are ready to go home, the radiation in your body will be much weaker. Your doctor will advise you if there are any special precautions you need to use at home.
High dose rate remote brachytherapy allows a person to be treated within a few minutes in inpatient or outpatient clinics. With remote brachytherapy, a very powerful radioactive source travels by remote control through tubes, or catheters, to the tumor. The radioactivity remains at the tumor for only few minutes. This procedure is done by the brachytherapy team, who will watch you on a closed-circuit television. They will talk to you through an intercom. In some cases, several remote treatments may be required. Sometimes, the catheter stays in place between treatments and sometimes it is removed, depending on your condition.
High dose rate treatments are short (usually a few minutes) and result in less discomfort than other types of radiation therapy. Because radioactive material are not left in your body, you can return home soon after you recover. Remote brachytherapy has been used to treat cancers of the cervix, breast, lung, pancreas, prostate, and esophagus.
What Happens After the Implant Is Removed?
- Usually, an anesthetic is not required while removing the implant. Most can be taken out right in the patient's hospital room. If you had to stay in bed during implant therapy, you might have to remain in the hospital an extra day or so after the implant is removed. Once the implant is removed, there is no radioactivity in your body. The nurses and your visitors no longer will have to observe any special rules.
Your doctor will tell you if you should limit your activities after leaving the hospital. Most patients are allowed to do as much as they feel like doing. You may need some extra sleep or rest breaks during your days at home, but should feel stronger quickly.
The area that has been treated with an implant may be sore or sensitive for some time after therapy. Your doctor may advise you to limit sports and sexual activity for a while if they cause irritation in the treatment area.