Brachytherapy is radiation treatment that is given inside the patient, as close to the cancer as possible. The radiation is delivered inside the body with radioactive isotopes (chemical elements), inside delivery devices such as wires, seeds, or rods. These devices are called implants.
Brachytherapy allows for a higher total dose of radiation over a shorter period of time than does external beam therapy. The radiation dose is concentrated on the cancer cells and less damage is done to the normal cells near the cancerous growth.
Brachytherapy may be performed in combination with external beam therapy to help destroy the main mass of tumor cells for certain types of cancer.
Brachytherapy is often used in the treatment of cervical, uterine, vaginal, prostate, or rectal cancer, as well as eye and certain head and neck cancers. However, the therapy may also used to treat many other cancers.
There are three types of brachytherapy delivery:
- intracavitary treatment - radioactive implants are placed inside body cavities such as the vagina, uterus, or breast.
- interstitial treatment - radioactive implants are placed directly into the tumor and may stay in the patient permanently.
- unsealed internal radiation therapy - a medication containing radioactive materials is injected into a vein or into a body cavity.
Brachytherapy implant placement may be one of two types:
- permanent brachytherapy
Also called low dose rate brachytherapy, permanent brachytherapy uses implants called pellets or seeds. These implants are very small, about the size of a grain of rice. The implants are inserted directly into a tumor through thin, hollow needles. The implants are left in place after the radiation has been used up, as their small size causes little or no discomfort.
- temporary brachytherapy
Temporary brachytherapy refers to the use of implants that are removed after the treatment has ended. Implants, such as hollow needles, catheters (hollow tubes), or balloons filled with fluid, are inserted into or near the cancer for a period of time, then removed. Either high-dose or low-dose brachytherapy may be used.
General anesthesia may be used during the insertion of implants, depending on the size and number of implants, as well as the location of the insertion site.
Generally, a person having brachytherapy will be treated on an inpatient basis, in order to protect others from the effects of the radiation while it is active inside the person's body. Although each facility may have specific protocols in place for the treatment of patients undergoing brachytherapy, generally, treatment protocols may include the following:
- placing brachytherapy patients in a private room
- limiting hospital staff time in the patient's room, but all necessary care will be given
- placing portable shields between the patient and staff/visitors
- limitations for visitors, which may include:
- pregnant women or children under a certain age should not visit
- a limit on the length of visits
- a limit on how close to get to the patient
How long the radiation lasts will depend on the type of treatment given. The physician will determine the brachytherapy type based on the type of cancer being treated, the location of the cancer, and other considerations. If the brachytherapy implant is a low-dose implant, the implant may be left in for several days. High-dose implants may be removed after only a few minutes.
Some implants are permanent and will be left in place. After placement of a permanent implant, a hospital stay of a few days may be required, depending on the dose of radiation and the location of the implant. The radiation becomes weaker each day, and the patient will mostly likely be discharged from the hospital in a few days. There may be certain safety measures to be taken at home. The physician will give specific instructions if necessary.
Temporary implants will be removed after the complete dose of radiation has been received.