CyberKnife® robotic stereotactic radiosurgery (SRS) painlessly delivers precise beams of high-dose radiation to brain tumors and lesions, without incisions, hospitalization, or long recovery time. CyberKnife SRS is a non-invasive alternative to brain cancer surgery and can be used for brain tumors that are considered inoperable because of their location in the head, for those patients who cannot undergo brain cancer surgery due to their poor medical condition, or who refuse surgery. The CyberKnife System also can treat benign, or non-cancerous, tumors and other conditions, such as trigeminal neuralgia and arterial venous malformations (AVMs).
CyberKnife® robotic radiosurgery painlessly delivers precise beams of radiation to tumors and lesions, without requiring incisions, hospitalization, or long recovery time. It can serve as an effective lung cancer treatment and is an especially good option for patients with complex tumors or patients who prefer a non-invasive way to treat their cancer.
Metastatic tumors occur when cancer cells from the primary cancer spread to other areas of the body. The most common areas cancer cells spread to are the brain, lungs, liver and bones. When cancer spreads to another area, it has the same name and the same type as the original cancer. For example, renal cell cancer that has spread to the lung is called metastatic renal cell cancer, not lung cancer.
The CyberKnife robotic radiosurgery system is a widely used form of nonsurgical prostate stereotactic body radiation therapy (SBRT). The American Society for Radiation Oncology (ASTRO) believes that enough clinical evidence exists so that SBRT should be considered an appropriate alternative for select patients with low- to intermediate-risk prostate cancer.
Radiosurgery for kidney tumors is noninvasive, and typically carries less risk of complications than conventional surgery. For patients who refuse surgery or have medically inoperable kidney tumors, radiosurgery can be an effective treatment option. CyberKnife, which delivers high-dose radiation over one to five treatments, can be particularly effective for treatment of small kidney tumors. CyberKnife has the ability to compensate for normal patient movements, precisely targeting the tumor during the entire procedure and minimizing damage to surrounding healthy tissue. This is important when treating kidney tumors, which can shift during treatment due to regular patient movements such as breathing.
CyberKnife’s ability to treat tumors with precisely focused radiation offers an important advantage for liver cancer patients. Accurate to within less than a millimeter, radiosurgery has minimal effect on surrounding health tissue. This level of accuracy enables doctors to target liver tumors with high-dose radiation, which significantly reduces the number of treatments needed – usually between three and five over several days compared to 30-40 over several weeks required for radiotherapy systems. Radiosurgery has other benefits as well, namely its ability to track tumors in real time. That means patients breathe normally during each treatment session, since the radiation beam adjusts automatically to the tumor location.
CyberKnife is capable of high-dose radiation for tumors or lesions in especially sensitive areas of the brain and is the only radiosurgery system that doesn’t need an invasive head frame. Radiosurgery with CyberKnife safely delivers high-dose radiation while minimizing exposure to healthy tissue. Ocular and orbital tumors can be difficult to treat due to their close proximity to important structures in the brain, and CyberKnife provides an effective treatment option for these tumors due to the precise nature of the radiation beams it delivers. Ocular and orbital tumors can greatly affect a patient’s quality of life, and radiosurgery with CyberKnife offers a treatment option that can preserve a patient’s vision.
CyberKnife treats pancreatic cancer with high-dose radiation. Clinical studies are ongoing to test the CyberKnife’s effectiveness in treating localized, non-metastatic pancreatic cancer. However, preliminary results involving patients with relatively advanced cases of pancreatic cancer suggest that CyberKnife radiosurgery treatment is well tolerated and provides some clinical benefit.
Prior to treatment, doctors implant between three to five small metal markers known as fiducials in or near the tumor that enable the CyberKnife to pinpoint the tumor location throughout treatment. Implanting the markers is an outpatient procedure that takes about an hour. About a week later, patients are fitted with a custom body mold made of soft material that they lie on during treatments. The fitting process is painless. Patients then undergo a CT scan that assists in developing a customized treatment plan.
Spine cancer is an abnormal growth of cells in or around the spinal cord resulting in a tumor. If the abnormal cells originated from cells in the tissues of the spine, this is a Primary Spine Tumor. Primary tumors in the spine are relatively rare and are either benign (non-cancerous) or malignant (cancerous).
If the abnormal cells originated in another part of the body, as in cancer originating in the lung, breast, colon or skin and were carried to the spine by the blood or other bodily fluid, growing into a tumor, then it is considered a Metastatic Spine Tumor.
Both primary and metastatic spine tumors are very serious because they can compress the spinal cord and/or destroy the bone and surrounding tissue in the spine. These tumors cause patients to experience pain, gait and posture problems, and other neurological issues.
What is CyberKnife®?
The CyberKnife System provides patients with a noninvasive treatment option for spine cancer. Unlike conventional radiation therapy, during which low doses of radiation are delivered over weeks and months, the CyberKnife System can treat a spine tumor in one to five days by delivering a high dose of radiation with extreme accuracy.
How does it work?
Spine tumors present a treatment challenge because they move as the patient breathes. Conventional radiation therapy cannot account for this movement, so surrounding healthy tissue may be damaged by the radiation. The CyberKnife System is able to achieve a high level of accuracy completely non-invasively – without the use of body frames or implanted fiducial markers. CyberKnife precisely targets the tumor’s exact location tracking and compensating for movement during treatment delivery. Using this method, the CyberKnife System is able to deliver a high dose of radiation to the tumor while avoiding damage to the surrounding sensitive spinal cord tissue and other critical structures.
During set-up and imaging, the patient may be fitted for a custom body cradle, which is designed to help keep the patient more comfortable and ensures the patient is in the same position for both imaging (CT or MRI) and treatment.
If the tumor is in the upper cervical region, the patient also may be custom-fitted with a mesh face mask. Both the cradle and face mask are painless and completely non-invasive.
While laying in the body cradle and/or wearing the face mask, the patient will undergo a computed tomography (CT) scan. This scan data will be used by the CyberKnife team to determine the exact size, shape and location of the tumor. A magnetic resonance image (MRI) or some other type of imaging study also may be needed to fully visualize the tumor and nearby anatomy. Once the imaging is done, the body cradle or face mask will be stored for use during treatment.
Treatment planning is then performed by a medical physicist in conjunction with the treatment team. The patient will not need to be present at this time. During treatment planning, all CT, MRI and other scan data will be downloaded into the CyberKnife System’s treatment planning software to develop a customized treatment plan. The medical team will determine the size of the area being targeted by radiation and the dosage, as well as identifying critical structures – such as the spine or vital organs – where radiation should be minimized. The CyberKnife System calculates the optimal radiation delivery plan to treat the tumor. The treatment plan will take full advantage of the CyberKnife System’s maneuverability, allowing for extremely accurate delivery of radiation.
After the plan is developed, the patient will return to the CyberKnife center for treatment. The doctors may choose to deliver the treatment in one session, or stage it over several days. Typically, treatments are completed in one to five days.
For most patients, the CyberKnife treatment is a completely pain-free experience. Patients dress comfortably in their own clothes and, depending on the treatment center, they may be allowed to bring music to listen to during the treatment. Patients also may want to bring something to read while they wait, and have a friend or family member with them to provide support before and after treatment.
What are the risks and side effects?
There are generally only minimal side effects from CyberKnife treatments. Occasionally patients report mild, temporary nausea, particularly if the lower abdomen is undergoing treatment. Prior to treatment, the doctor will discuss with the patient all possible side effects they may experience. The doctor also may prescribe medication designed to control any side effects should they occur. Patients may return to their normal activities after treatment.
How effective is it?
After completing the CyberKnife treatment, patients should schedule and attend all follow-up appointments. Patients must keep in mind that the tumor will not suddenly disappear. In fact it could take several months, or longer, to determine the effectiveness of the CyberKnife treatment. Response to treatment varies from patient to patient. Clinical experience has shown that most patients respond very well to CyberKnife treatments. By routinely evaluating the symptoms and undergoing post-operative MRIs, the doctor can chart the patient’s post-treatment progress.
How does CyberKnife® treat trigeminal neuralgia?
CyberKnife is a non-invasive alternative to surgery for TN. High-dose radiation is accurately delivered by a linear accelerator mounted on a highly maneuverable robotic arm. The procedure is painless and typically performed in one outpatient treatment session. Unlike other stereotactic radiation therapy treatments for TN, the CyberKnife does not use a rigid metal frame secured to the patient’s head with screws. Instead, TN patients wear a comfortable mesh face mask. The CyberKnife delivers hundreds of highly concentrated and incredibly precise beams of radiation targeted directly to the trigeminal sensory nerve root, interrupting the transmission of pain signals to the brain.
How does it work?
The CyberKnife system uses a highly advanced computer-imaging system that can compensate for small head movements, allowing the patient to lie comfortably during the procedure.
Before treatment, the patient wears a light, flexible, and completely non-invasive mesh mask. The mask is fitted so that the patient is comfortable and able to breathe normally, see, and lie still during the treatment.
During treatment, the patient lies still and relaxes as the CyberKnife’s computer-controlled robotic arm moves around the head area, delivering high-dose radiation directly to the trigeminal nerve root and minimizing radiation to surrounding areas.
After treatment, patients resume their normal activities.
What are the risks and side effects?
CyberKnife treatment results in few to no side effects, with the most common being fatigue. The vast majority of CyberKnife treatments allow patients to resume their normal routines afterward. Some patients actually take naps during their treatments while others have reported going to lunch or mowing their lawns following treatment.
How effective is it?
As numerous clinical studies show, CyberKnife offers an effective treatment option for TN while carrying an extremely low likelihood of negative side effects. CyberKnife’s ability to treat the trigeminal nerve root at an extremely precise level makes it an effective and non-invasive way to treat TN.