Radiation Oncology: Brachytherapy

Doctor explaining something to patient

Brachytherapy delivers radiation by placing radioactive material inside your body, either directly inside a tumor or very close to it. This method, sometimes called internal radiation, spares healthy tissue by allowing radiation to be delivered to a specific area of the body. Brachytherapy allows your doctor to use a higher total dose of radiation over a shorter time than is possible with external beam therapy. Radiation is delivered at a low-dose rate over a period of weeks or months, or at a high-dose rate during a short period of time. The method used depends on the placement of the radioactive material.

Conditions treated with this procedure include:

  • Brain tumors
  • Head and neck cancer
  • Gynecologic cancer
  • Prostate cancer
  • Esophageal cancer
  • Liver cancer

Low-Dose Rate

Low-dose rate (LDR) brachytherapy delivers radiation over time, typically a period of weeks or months.

Small radioactive pellets, often called "seeds," each about the size of a grain of rice, are implanted into the tumor. These seed implants contain radioactive isotopes such as iodine 125 or palladium 103. The seeds are inserted directly into a tumor with thin, hollow needles. The seeds are left in place after the radiation has been used up. Their small size causes little or no discomfort.

This is an outpatient procedure and most patients are able to go home the same day.

Our radiation oncologists and urologists are experts in LDR brachytherapy for prostate cancer. Many of our patients with prostate cancer are candidates for this curative treatment.

Our radiation oncologists and neurologists also specialize in central nervous system brachytherapy for cancer that has spread to the brain and other brain tumors. During surgery to remove a brain tumor, neurosurgeons and radiation oncologists work together to carefully place the seeds in the targeted area.

High-Dose Rate

High-dose rate (HDR) brachytherapy is most commonly used to treat prostate, cervical, and head and neck cancer. During the procedure, radioactive material such as iridium, is temporarily placed in the tumor. The radioactive material travels through implants, typically small plastic catheters, to the targeted area. The implants are then removed after the treatment has ended.

A specialized computer system aids in determining the precise location. This allows for customized dose distributions to meet a patient's specific needs.

Recent technological advances at GW have led to breakthroughs in the delivery of HDR brachytherapy. Computerized tomography (CT), magnetic resonance (MR) image guidance, and clinical expertise create the optimal dose distribution.

The brachytherapy treatment team at GW includes a radiation oncologist, surgeon, physicist, radiation therapist, and nurse. Together they offer the most comprehensive brachytherapy program in the Washington, D.C., metropolitan area.


Our radiation oncologists and interventional radiologists also perform radioembolization (Y90 Theraspheres or SIR-Spheres) for the treatment of liver cancer or tumors that have spread to the liver. This treatment involves infusing microspheres containing the radioactive isotope Yttrium 90 into the blood vessels that feed the tumor. This blocks the supply of blood to the cancer cells and delivers a high dose of radiation while sparing normal tissue. It can help extend the lives of patients with inoperable liver tumors and improve quality of life.

How does brachytherapy work?

Brachytherapy can be given in three ways:

  1. Interstitial treatment (needle implant): Implants are placed directly into the tumor and may remain permanently. Needles are placed throughout the site and a single radioactive seed travels through each needle into the tumor to deliver the prescribed dose. This method involves a week-long series of outpatient treatments.  
  2. Intracavitary treatment (balloon implant or MammoSite RTS Balloon): Implants are placed inside body cavities such as the vagina, uterus, or breast. The MammoSite brachytherapy balloon is similar to the needle implant. Instead of needles being implanted in the breast, the radiation is delivered through a balloon implant placed in the cavity at the time of surgery or re-excision.  
  3. Unsealed internal radiation therapy: A medicine with radioactive materials is injected into a vein or into a body cavity.

Brachytherapy implant placement may be either permanent or temporary:

  • Permanent brachytherapy: This is 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 seeds are inserted directly into a tumor through thin, hollow needles. The seeds are left in place after the radiation has been used up. Their small size causes little or no discomfort. 
  • Temporary brachytherapy: In temporary brachytherapy, implants 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 or local 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, you will be treated on an outpatient basis when you have brachytherapy. If you receive high- dose rate therapy, you will be in the hospital for a few days. You will need to follow specific rules to protect others from the effects of the radiation while it is active inside your body

How long does the radiation last?

How long the radiation lasts will depend on the type of treatment given. Your doctor will determine the brachytherapy type based on the type of cancer you have, the location of the cancer as well as other factors.

If the brachytherapy implant is a low-dose, it may be left in for several days. High-dose implants may be removed after only a few minutes. Some implants are permanent. If you have one, you may need to stay in the hospital. The radiation gets weaker each day and you will likely be discharged from the hospital after a few days. There may be certain safety measures to be taken at home.

Temporary implants may be removed after you have received the complete dose of radiation.

Contact Us

For brachytherapy, contact GW Radiation Oncology

Main Phone: (202) 715-5097

Fax: (202) 715-5136