Your doctor may recommend internal radiation therapy (brachytherapy) as the best way to treat your cancer. Instead of using radiation beams aimed from a large machine, a radioactive material is placed directly into, or as close as possible to, the cancer. This type of radiation travels a very short distance in the body (“brachy” is a Greek prefix for “short”). The material is placed so that it harms as few normal cells as possible. The material itself may be left in the body for only a short time, or it may be left there permanently.

Internal radiation therapy allows your doctor to give a dose of radiation to a smaller area and in a shorter time than is possible with external radiation treatment.

The main types of internal radiation are intracavitary radiation and interstitial radiation. Both of these methods involve using radioactive material that is sealed in small containers (implants), such as metal pellets (“seeds”), wires, needles, or tubes. During intracavitary radiation, the material is placed in a cavity (space) in the body such as the uterus. With interstitial radiation, the implants are placed into or near the cancer, but not in a body cavity.

Another type of internal radiation therapy uses materials that travel throughout the body. These unsealed radiation sources are usually in the form of a liquid. They can be injected into the bloodstream or in a body cavity. Some are given by mouth. They are designed to collect in a certain area of the body, where they give off their radiation.


How Is the Implant Placed in the Body?

Sealed radioactive substances are placed in body cavities or body tissue with applicators, which are metal or plastic tubes. This is done in a hospital operating room. Before the placement of the applicator(s), you will get anesthesia, which may be either general (where you are asleep) or regional (where part of your body is numbed). Applicators are placed either during surgery or by a doctor using an imaging test (such as an x-ray or MRI) to look at the intended location. If the applicators need to be held in place, stitches may be used.

During the actual treatment, the implants are placed into the body through the applicator(s). Some implants are permanent, while others are left in for a brief time. The applicator may be removed at the same time as the implant, or it may be left in place until all of the treatments are finished.


How Long Do Implants Stay in Place?

The type of implant you receive and your treatment schedule will depend on the type of cancer, where it is in your body, your general health, and other treatments you have had. Some implants deliver low doses of radiation and are left in place for several days (or more). Others deliver high doses of radiation and are removed after only a few minutes.

Some low-dose implants are left in place from 1 to 7 days. For larger implants, depending on where the implant is placed, you may have to stay in a hospital bed and lie fairly still to keep it from moving.

Some smaller implants (such as the “seeds” used to treat prostate cancer and some lung cancers) may be left in permanently. They stop giving off radiation, usually over the course of several weeks. The seeds that remain in the body are about the size of rice grains and do not usually cause problems. If your implants are to be left in, you may be able to go home the same day they are inserted (or the day after). But you will need to stay in the treatment center until the anesthesia wears off.

High-dose-rate (HDR) brachytherapy allows a person to be treated for only a few minutes at a time with a powerful radioactive source that is placed in the applicator. The source is removed after only a few minutes. This may be repeated over the course of a few days to weeks. The radioactive material is not left in your body.


How Will I Feel During Implant Therapy?

You are not likely to feel severe pain or become ill while implants are being put in. The anesthesia used during the placement might make you feel drowsy, weak, or nauseated, but these side effects do not last long. If your implant is held in place by an applicator, you may have some discomfort. Ask for medicine to help you relax or to relieve pain if needed. Be sure to tell the nurse if you have any burning, sweating, or other symptoms.


What Happens After the Temporary Implant Is Removed?

Usually, anesthesia is not required when the implant is removed, and most can be taken out right in your hospital room. The treated area may be sore or sensitive for some time after treatment, but most patients can return to normal activities quickly. Keep in mind that your body is recovering, and you may need extra sleep or rest breaks over the next few days.


What Happens to Permanent Implants?

Radioactive material will stop giving off radiation after weeks or months. Once the radiation is gone, the implant capsules become inactive. Usually they remain in place and cause no harm, and they do not need to be removed.


Will I Be Radioactive During or After Treatment?

External radiation therapy affects cells in your body only for a moment. Because there is no radiation source in your body, you are not radioactive at any time during or after treatment.

With internal radiation therapy, your body may give off a small amount of radiation for a short time.

If the radiation is contained in a temporary implant, you will be asked to stay in the hospital and may have to limit visitors during treatment. Pregnant women and children may not be allowed to visit. With sealed sources, body fluids and materials used by the patient are not radioactive.

Permanent implants give off small doses of radiation over a few weeks to months as they slowly stop giving off radiation. The radiation usually doesn’t travel much farther than the area being treated, so the chances that others could be exposed to radiation is very small. Still, your health care team may ask you to take certain precautions such as staying away from small children and pregnant women, especially just after you get the implants.

If you have an unsealed radioactive substance such as iodine, phosphorus, or strontium by mouth or into a vein, some radiation will remain in your body for a few days, until your body has had a chance to get rid of it. You may also pass it in your urine, saliva, blood, or other body fluids. You may be asked to stay in the hospital for a day or two, and your health care team will tell you what precautions to take until your body no longer contains radiation that might affect others. Be sure to discuss any safety concerns you have and precautions you need to take with them. These precautions vary depending on the substance used.

Revised: 10/02/2007