HDR Brachytherapy Provides Powerful, Internally Delivered Radiation Therapy
It has a complicated mouthful of a name. But high-dose rate (HDR) HDR brachytherapy is based on a simple premise: Delivering concentrated doses of radiation inside the body and directly to the tumor site can be a highly effective treatment, with less damage to healthy tissue.
Typically, radiation therapy, which can be used to shrink a tumor before surgery or to destroy any cancer left behind after surgery, is administered externally to the tumor area.
But by delivering radiation internally, HDR brachytherapy, which Rocky Mountain Cancer Centers offers at its Thornton location, deposits radiation directly to the tumor site. While the theory behind the technique may be simple, the technology that makes it possible is highly advanced, says Rocky Mountain Cancer Centers radiation oncologist Daniel Chin, MD.
During treatment, tiny, hollow catheters are temporarily inserted directly into the tumor or tumor site. Before each treatment, Rocky Mountain Cancer Centers radiation oncologists determine the proper position of the catheters with millimeter precision.
Next, a series of radioactive pellets are inserted into each catheter. Computer guidance controls where the radiation is delivered, and how long the pellet stays in the catheter to release its radiation dose.
At Rocky Mountain Cancer Centers, HDR brachytherapy is used most often to treat gynecologic cancers, as well as skin and bile duct cancers, Chin says. Elsewhere, it frequently also is used for breast, prostate, esophageal cancers, and in some cases to treat soft-tissue sarcomas and cancers of the bronchial passageways, he says.
How does HDR Brachytherapy Work?
HDR brachytherapy works on the same principle as external radiation therapy. That is, it damages the genetic material of cancer cells, preventing the cells from growing and multiplying.
But the delivery system HDR brachytherapy employs gives it certain advantages, Chin says. “The correct radiation is delivered precisely, directly to wherever the tumor is,” he says. “It is a more focused area, so we don’t have to radiate a large area, and there are fewer side effects.”
In addition, the precision allows patients to receive higher doses of radiation. Often, HDR brachytherapy is used in addition to external radiation. But in certain uterine and endometrial cancers, HDR brachytherapy can be used, after surgery, in place of external radiation. Those patients can get the same benefit with fewer treatments. “Typically, we do three to five treatments, each high-dose, compared with about 25 treatments with external radiation,” Chin says.
HDR brachytherapy isn’t an option for every patient who needs radiation, Chin says. “Sometimes, we do need to treat a larger area, or lymph nodes that are at risk. That can only be done with external radiation.”
But when it’s appropriate, “HDR brachytherapy offers effective therapy in fewer treatments, with fewer side effects,” Chin says.