The term “brachy” means short distance. Brachytherapy is a type of radiation therapy that refers to the use of sealed radioactive sources inside or at a short distance from a malignancy.
Low Dose Rate Brachytherapy (LDR)
Radioactive sources have been used in medicine since the discovery of radioactivity. Classically, because of technical difficulties in the production of high-intensity sources, most of the experience accumulated in the treatment of cancer with this modality of treatment was obtained with low-intensity sources, giving rise to the term low dose rate brachytherapy.
This form of therapy is usually performed in a hospital setting, requiring radioactive “seeds” to be surgically implanted in or near the patient’s tumor, delivering a higher dose of radiation to the tumor and keeping the dose to the normal surrounding tissues to a minimum. This would not be possible if the same dose of radiation was given with external beam therapy.
This form of treatment is used in several gynecologic tumor settings. It is also commonly used to treat prostate cancer, where it is often called a Prostate Seed Implant.
MRO physicians have pioneered the use of Prostate Seed Implants in the Upper Midwest. The treatment was first performed in the region by MRO physician Dr. Doug Olson in 1988.
The prostate brachytherapy procedure is performed in a specially-equipped operating room by the radiation oncologist and an urologist. The patient is asleep under general anesthesia throughout the procedure. Working closely together, the team uses ultrasound guidance to place long thin metal tubes into the prostate, through which 70-120 tiny radioactive seeds are placed. The seeds are about the thickness of a pencil lead and just over 1/8 inch long. The procedure typically takes one hour, and the patient is typically discharged later that day.
Although the internal seeds emit low-energy radiation with only trace amounts of radiation outside the patient’s body, all facilities performing brachytherapy recommend patients avoid close contact with children and pregnant women for a short time following seed placement. The seeds are essentially inactive and no longer give off radiation after approximately six months. They can be safely left in place indefinitely.
High Dose Rate Brachytherapy (HDR)
Devices called high dose rate remote afterloading machines allow radiation oncologists to complete brachytherapy quickly, in about 10 to 20 minutes. Powerful radioactive sources travel through small tubes called catheters to the region of the tumor for the amount of time prescribed by your radiation oncologist. You may be able to go home shortly after the procedure. Depending on the area treated, you may receive several treatments over a number of days. These treatment techniques are often used for gynecologic cancers.