High Dose Rate Brachytherapy

In the treatment of most malignancies with radiation therapy Brachytherapy plays a very significant role. Brachytherapy entails the placement of radioactive source in a cavity (intracavitary therapy) in close proximity to the tumor or in the tissues themselves (interstitial therapy) to deliver a high dose of radiation to a limited volume. Traditionally the dose of radiation is delivered at a rate of about 40 to 70 cGy per hour, Low Dose Rate (LDR), thus requiring anywhere from several hours to a few days to deliver a significant dose of radiation to a tumor bearing area.

 

Recently radioactive sources with very high specific activity have become available, such as iridium, which deliver a high dose of radiation in a very short period of time. This is referred to as High Dose Rate (HDR). The HDR unit is small, self contained and can be moved about. While the unit is not in use, the radioactive source is in the safe and poses no risk of radiation exposure.

 

During a procedure the radioactive source is out the of the safe and there is the risk of radiation exposure to the health care personnel. To avoid this the procedures are often carried out with the patient in an existing, shielded accelerator room with the health care personnel outside of the room. Having a HDR unit in a shielded booth adjacent to the operating room would expand the utilization of this resource. Having the unit in an area adjacent to the operating rooms would permit using it for patients that are found to have gross or microscopic residual disease at surgery. At the time of surgery catheters can be placed in the area of the tumor and with the patient still under anesthesia the patient is brought to the booth adjacent to the operating room. With the catheters in place the radioactive source is passed through the catheters for the specified time necessary to deliver the desired dose of radiation. This unit can also be used for some of the cases currently being done with conventional, LDR radioactive sources.

 

Currently about 80 interstitial/intracavitary procedures are performed in a calendar year and it is estimated that 1/3 to 1/4 of the procedures could be performed with the HDR unit. By having this resource available it is anticipated and a few more procedures will be performed due to increased utilization of this resource as well as possible increased referral of patients for this procedure.

 

HDR does not replace LDR Brachytherapy but it expands this type of resource. The advantages of HDR consist of: avoidance of radiation exposure to the health care personnel; significant reduction of the duration of the procedure making this more comfortable for the patients and in some instances becoming an oupatient procedure and the possibility combining this with a surgical procedure.

 

Other Treatment Options

• 3D/Conformal Radiation Therapy
• Eye Plaques
• High Dose Rate Brachytherapy
• Hyperthermia
• Intra-Operative Radiotherapy
• SRS
• Gated Therapy
• Image-guided radiation therapy (IGRT)
• Intensity-modulated radiation therapy (IMRT)
• Stereotactic body radiation therapy (SBRT)
• Prostate Seed Implant (PSI)
• Total-body irradiation (TBI)
• Total Skin Electron Beam (TSEB)
• Low-Dose Radiation (LDR) Brachytherapy