Brachytherapy (from the Greek brachy, meaning "short")
Pronounced “brack-ay-therapy,” the treatment involves placing radioactive material inside or near a tumor. This allows radiation to conform to the size and shape of the tumor or organ while minimizing radiation to the rest of the body. Brachytherapy when performed well can conform radiation better than external beam radiation.
LDR (Low Dose Rate) Brachytherapy is the most common form of brachytherapy used to treat prostate cancer. It involves an outpatient surgical procedure where tiny radioactive particles smaller than a grain of rice – “seeds” – are implanted directly into the prostate. Each seed emits radiation and then remains in the prostate as an inert shell. LDR brachytherapy can be used in conjunction with external beam therapy if higher doses of radiation are required.
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HDR (High Dose Rate) Brachytherapy involves placing tiny hollow plastic catheters into the prostate gland. The catheters are placed into the prostate in the operating room under anesthesia. Radiation treatments are then given via these catheters. A computer-controlled machine pushes a single highly radioactive iridium seed into the catheters one by one. Because the computer can control how long this seed remains in each of the catheters, we are able to manage the radiation dose in different regions of the prostate. This ability to modify the dose during treatment is one of the advantages of HDR brachytherapy. We can give the tumor a higher dose while sparing the bladder and rectum. Once the treatment is completed the catheters are removed leaving nothing in the prostate and the patient goes home. Like LDR brachytherapy, HDR brachytherapy can be used in conjunction with external beam therapy in select patients.
As you have read, both LDR and HDR are forms of brachytherapy whereby the radiation source is placed inside the prostate.
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Treatment That’s Withstood the Test of Time
The backbone of all medical advances is scientific research, which utilizes randomized experimental trials to determine the effectiveness of treatment, optimize dosing, and minimize complications. The Radiation Therapy Oncology Group (RTOG) has largely carried out the major radiation therapy studies. These trials have set the benchmark for modern radiation therapy in prostate cancer. The results of these trials, which determine guidelines for radiation therapy treatments utilized in actual patients, are based on radiation therapy delivered with a linear accelerator like the Varian family of products. Of the external beam radiation therapies available in Truckee Meadows, the Varian system is the most established technology.
As you can see, the use of radiation therapy for prostate cancer is a complex topic. No single form of radiation therapy has been proven to be the best solution for all patients. When considering which treatment is appropriate for a given patient one must consider the characteristics of the cancer and the prostate itself (size, aggressiveness, anatomy) as well as the patient’s characteristics (age, health, current urinary, bowel and sexual status).
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