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CyberKnife is a noninvasive alternative to surgery for treating cancerous and noncancerous tumors anywhere in the body. CyberKnife delivers beams of high-dose radiation to tumors with extreme accuracy, offering hope to patients whose tumors were previously inoperable.

CyberKnife treatment involves no incision. In fact, it is the world's first and only robotic radiosurgery system designed to noninvasively treat tumors throughout the body.

How CyberKnife Works

CyberKnife radiosurgery delivers radiation with extreme accuracy. It targets the tumor with minimal exposure to the surrounding healthy tissue. Unlike surgery, CyberKnife does not remove tumors or lesions, but delivers a precise dose of radiation that destroys tumor cells and spares surrounding tissue.

CyberKnife is a frameless radiosurgery system consisting of integrated parts. The central component is a lightweight linear accelerator mounted on a robotic arm. The mobility of CyberKnife enables it to treat tumors and lesions from a variety of angles without clinician intervention or treatment interruption.

The radiation beams from CyberKnife adjust in real-time to a patient's breathing cycle. Many tumors, even when their movement has been restricted, continue to move during treatment delivery. CyberKnife's advanced robotic technology and ability to track tumor movement throughout the treatment, allows it to deliver radiation with extreme accuracy.

By dramatically reducing the planning margins and accounting for patient movement, CyberKnife minimizes damage to the surrounding healthy tissue.

The Advantage to Patients

  • Noninvasive, so no incision, no pain and no blood loss
  • Treats hard-to-reach tumors, including many that cannot be treated with conventional surgery
  • Does not require anesthesia
  • Performed as an outpatient procedure
  • Quick return to normal activity
  • Effective for lesions previously treated with radiation therapy

Types of Cancer Treated with CyberKnife

Currently, CyberKnife is being used by Penn Medicine to treat:

What to Expect

Consult Visit

If you are being considered for CyberKnife treatment, you will meet with a physician within a week of making the initial call. During this meeting, the physician reviews your case and develops a care plan that addresses the best way to treat the cancer. The plan may include CyberKnife treatment alone, CyberKnife in conjunction with other techniques or a different treatment option. If CyberKnife therapy is chosen and approved, the doctors and physicists at Penn will develop an individualized treatment plan for you.

CT Simulation

During the CT simulation, the radiation oncologist obtains a 3-D picture of the tumor using CT, MRI or PET scanning. This information is used to reconstruct the tumor and the adjacent normal structures, allowing for accurate and precise dose targeting to the tumor and projection of normal tissues. In some cases, patients may require an outpatient procedure to place fiducial seeds (gold seeds) prior to CT simulation. These seeds help the CyberKnife track the actual movement of the target area.

Prior to starting radiation therapy, patients participate in a "dry run." The dry run usually takes place in the actual treatment room and all aspects of the patient's prescribed treatment are checked for accuracy.

CyberKnife treatments typically start five to ten days following treatment planning.

Treatment Sessions

CyberKnife treatments last an hour to two hours based on the type of tumor being treated. Because CyberKnife delivers precise radiation to the tumor, treatment can be completed in one to five days. The frequency of treatments depends on the type of tumor and where the tumor is located. Unlike some other types of radiation therapy, patients can receive multiple treatments or can have their cancer retreated with CyberKnife.

Follow up

At the completion of their CyberKnife treatment, patients are scheduled for a follow-up visit with their radiation oncologist. During this appointment, they are encouraged to talk about any problems they are experiencing with pain or symptom management. Patients are also encouraged to discuss any other challenges they are experiencing (emotional, social, work/life) as a result of their diagnosis or treatment. The follow up typically takes place a month after treatment ends.

Most patients experience minimal or no short-term side effects from CyberKnife treatment and often recover quickly. Depending on the treatment site, some patient's may experience mild fatigue or nausea. The Penn radiation oncologist discusses all possible side effects prior to treatment.

The effects of radiosurgery vary and may occur gradually and over time, from days to years after treatment, depending on the medical condition. Some tumors may disappear slower than others or may simply stop growing and present no further cell activity. After treatment, patients receive a summary of their treatment and a follow-up care plan. This includes recommendations for screening for disease recurrence and so the physician can monitor the effectiveness of the treatment.