CyberKnife Offers Targeted, Painless And Fast Treatment

By Allyson Ger



A new radiosurgical tool will allow physicians at Georgetown University Hospital to provide targeted, painless and accurate treatment of tumors and other lesions. The device, known as the CyberKnife Stereotactic Radiosurgery/ Radiotherapy System, is a robotic-controlled linear accelerator that delivers pinpoint radiation to reduce or eliminate benign and metastatic tumors and arterio-venous malformations throughout the body.

The addition of the CyberKnife to the Neurosurgery and Radiation Medicine departments means that physicians can offer tumor patients new treatment regimens that were not possible in the past. While stereotactic radiosurgery for tumors of the brain has been possible for more than a decade, the CyberKnife is uniquely capable of irradiating lesions of the spine and even spinal cord with millimeter accuracy, according to Fraser Henderson, M.D., director of the Spine Tumor Center. "CyberKnife has given us the ability to comprehensively treat multiple lesions throughout the nervous system and spine. The patients can undergo open surgery and then radiosurgery of the non-operative lesions in one hospitalization."

One of the main features of the new system is the flexible robotic arm, which provides unparalleled access to previously unreachable tumors and reduces harm to the critical structures surrounding the lesion. "After careful planning, the precise robotic arm can stretch to hard-to-reach areas in parts of the body exactly where the tumor is located," said Walter Jean, MD, Neurosurgery. Jean was one of several Georgetown physicians who received extensive training in operating the CyberKnife at Stanford University Medical Center. The precise radiation delivered by the arm then "minimizes the chance of injury to the critical structures surrounding the tumor," he explained.

Unlike other radiosurgical devices, the CyberKnife does not require an invasive stereotactic head frame, such as the one commonly used for the Gamma Knife procedure, which beams gamma-ray radiation to the patient through a hemispheric helmet. CyberKnife relies instead on an advanced near-real-time image guidance system, which uses bony landmarks or implanted markers as a reference system, eliminating the need for rigid immobilization. "Patients do not get bolted to a head frame," Jean added.

The absence of a head frame means that doctors can treat other types of tumors. While the Gamma Knife use is limited to the brain, the CyberKnife can target lesions throughout the body. Currently, CyberKnife has FDA approval to treat other tumors and conditions of the brain, base of skull, head, neck, spine and other areas of the body where radiation may be indicated.



How Does It Work?

A patient considered for CyberKnife surgery is first assessed extensively by a team comprising a treating neurosurgeon, radiation oncologist and physicist to determine whether radiation is appropriate and how much. Sophisticated software then allows for complex radiation dose planning in which critical structures - eyes, spinal cord, kidneys and gastrointestinal tract - are identified and protected from harmful levels of radiation dose. At Georgetown, the CyberKnife will initially be used for brain and spine tumors.



CyberKnife Training

With its first patients in March, Georgetown became the first hospital in the Washington metro area to offer clinical use of the CyberKnife. And, preparing for this CyberKnife surgery was no easy task. Earlier this year, a team of six doctors participated in extensive training in the technical aspects and medical utilization of the machine. During the training, conducted by Stanford neurosurgeons and product engineers, doctors learned everything from how to understand the CyberKnife's actions to determining the types of tumors that are appropriate for this treatment. This month, a handful of voluntary faculty physicians will participate in a CyberKnife training session led by the Stanford group as well. More in-depth training for additional physicians will continue later this year.

Georgetown is the sixth academic hospital worldwide to operate the CyberKnife. This tool, said Jean, has dramatically enhanced the level of care that can be offered to tumor patients. The development of the CyberKnife program represents a major advance in terms of unifying the diagnostic, radiation, oncological and surgical management of cancer.

"Third millennium treatment of cancer requires multidisciplinary management," said Henderson. "Our goal is to closely collaborate with radiation oncology and to return patients as quickly as possible to their former chemotherapy treatment regimens and quality of life."

Georgetown University Hospital is a member of the MedStar Health family.



For more information on the CyberKnife, call Physician Access at Georgetown University Hospital at 202-342-3300.