High-dose rate (HDR) brachytherapy is a cancer treatment that delivers high levels of radiation directly into or near a cancerous tumor. It can be used to treat several cancer types, and it decreases or eliminates many common adverse side effects of radiation therapy, such as post-treatment infections and delivering radiation to healthy tissues. Despite its effectiveness and benefits, few cancer patients are candidates for HDR brachytherapy.
Radiation therapy, or radiotherapy, is a cancer treatment option that destroys cancer cells and is delivered externally or internally. When delivered externally, a machine outside the body directs radiation at the diseased area. Brachytherapy treatment is the internal method, delivering radiation directly into or near cancerous tissue. The term brachytherapy means short-distance therapy, denoting how far the radiation must travel compared to external radiation therapy.
Internal radiation treatment can be further divided into two types: low-dose rate (LDR) and high-dose rate (HDR) brachytherapy. LDR brachytherapy constantly delivers low doses of radiation for a period of days and even months. HDR brachytherapy patients, however, receive high levels of radiation for minutes at a time over a shorter period. HDR brachytherapy is sometimes referred to as temporary brachytherapy because the radiation source and its delivery device are always removed, which is not the case with some types of LDR brachytherapy.
The process of HDR brachytherapy is essentially three-fold. First, cancer specialists implant catheters into or around the patient's diseased tissue. Radiation is then delivered through the catheters from a machine outside of the body. After several minutes, the radiation source is removed, but the catheters remain implanted until the patient has completed the entire treatment. The duration of each session and the overall treatment depends on many factors, such as the cancer type and location.
Compared to external radiation therapy, HDR brachytherapy has many benefits for both patients and medical professionals. As a short-term and often outpatient treatment, it is especially helpful for those patients who must undergo other types of cancer treatment concurrently or after completing HDR brachytherapy. Delivering radiation internally also limits healthy tissue's exposure to harmful radiation, which further decreases other possible complications and speeds recovery. In addition, HDR brachytherapy offers an option for those patients whose cancer requires immediate and aggressive radiation treatment. Finally, cancer treatment specialists have little risk of radiation exposure because, once the radiation source is removed from the catheter, patients are no longer radioactive.
HDR brachytherapy can be used to treat many cancers, including those of the lung, esophagus, and anorectal areas. In particular, it has shown promising results in the treatment of cervical and prostate cancer, sometimes preventing the need for surgery. Still, as of 2009, the Department of Radiation Oncology at Loyola University Chicago reports that only a very small percentage of cancer patients are candidates for brachytherapy.