New procedure could offer a safer, more convenient treatment for spine tumors
The UCI researchers collaborated with a colleague from St. Jude Heritage Medical Group in
"With further development, this technology may yield a clinically feasible procedure that would eliminate the need for 10 radiation therapy sessions, making it more convenient for the patient," says Dr. Keyak, an associate professor in UCI's department of orthopaedic surgery. "This procedure would also deliver a higher dose to the bone metastases and a lower dose to the spinal cord and other normal tissues than conventional external beam radiation therapy, potentially improving the clinical outcome," she explains. "The negligible dose to the spinal cord would also make it possible to treat recurrent spinal tumors in patients who have already received the maximum allowable radiation dose to the spinal cord."
According to the American Cancer Society, almost 185,000 people in
Spinal metastases can cause pain and vertebral collapse. And, due to the proximity of the spinal cord and nerves, those tumors can lead to serious neurological complications. Conventional treatment often occurs in two phases:
- A surgical procedure (vertebroplasty or kyphoplasty) in which bone cement is injected into the body to stabilize the bone
- Subsequent external beam radiation therapy (or EBRT) to control tumor growth
The effectiveness of EBRT for spinal metastases is limited because the spinal cord restricts the dose of radiation that can be safely delivered. In addition, EBRT is typically provided in multiple sessions to reduce toxicity to the spinal cord, making treatment inconvenient for the patient.
The therapy investigated by Dr. Keyak and her colleagues would combine the two treatment phases into one procedure by mixing a radioactive compound with the injected cement. A single procedure using this radioactive bone cement would provide structural reinforcement to the bone while simultaneously irradiating the tumor from within (i.e., vertebral brachytherapy). Results of the study showed that a therapeutic dose of radiation would reach the intended bone without undue risk to tissue beyond a certain range (such as the spinal cord).
Once the results are validated, subsequent studies will look at the following:
- Refining the choice of radioisotope(s), amount of activity and geographic distribution of the cement
- Sensitivity of the radiation dose distribution to variations in bone size, density and tumor type; differences in bone cement formulations; and other factors associated with a potential clinical application
An abstract of the study is available online at http://www.ors.org/web/Media.asp.
For more information about the Orthopaedic Research Society, visit the ORS Web site (http://www.ors.org/web/about_the_ors/welcome.asp).
SOURCE Orthopaedic Research Society