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When you choose CyberKnife treatment, you can rest assured that you're getting one of the most advanced treatments for cancer available—and the nation’s most experienced CyberKnife experts. Though it sounds like a surgical procedure, CyberKnife is actually a painless and non-invasive form of radiation that offers accurate, effective treatment for tumors anywhere in the body—even in places previously considered unreachable. CyberKnife uses a combination of computers, image-guided cameras, and robotic technology to concentrate radiation directly at tumor cells, while limiting radiation exposure to surrounding healthy tissue.

How it Works

CyberKnife® is one of the most advanced and effective stereotactic radiosurgery technologies, which is a method of controlling or destroying tumors by aiming beams of radiation at them from multiple directions. Multiple X-ray cameras and powerful software pinpoint the exact location of a tumor. A robotic arm then points a linear accelerator directly at the tumor from more than 1,400 different angles, aiming high-powered radiation beams at it. Because the robotic arm has unparalleled flexibility, the beams of radiation can be directed even at difficult-to-reach areas of the body. And, because the beams are so precise, they focus only on the tumor, and minimize dose to healthy surrounding tissue.

CyberKnife Treatment 

CyberKnife is a valuable treatment, but the right use depends on several factors. Our program offers:

  • Team Approach: Top CyberKnife treatment depends on a group of specialists coordinating with each other. Our close-knit team has worked together for years, providing accurate diagnoses, thorough evaluations and individualized plans. While one doctor guides you through the process, our team includes:
    • Radiation oncologists
    • Surgeons
    • Physicists
    • Dosimetrists
    • CyberKnife therapists
    • Radiation oncology nurses
    • Urologists
    • Neurosurgeons
    • Gastroenterologists
    • Pulmonologists
  • Experience: We were the first East Coast center to adopt CyberKnife and remain among the most experienced users in the world. We continue to pioneer and expand the ways CyberKnife can treat tumors.
  • Clinical Trials and Research: We’re one of the few centers in the country that continues to study CyberKnife for new and improved uses. That means access to clinical trials that could help your condition and that aren’t available elsewhere.
  • Additional Support: We also offer a full range of support services:
    • Special pain control service
    • Nutrition counseling
    • Speech and swallowing therapy (for head and neck cancers)
    • Social work
    • Psychiatry


A team of physician specialists and radiologists offer every patient we see the most thorough evaluations, accurate diagnoses, comprehensive treatments, and advanced technologies available. While, our specialists customize CyberKnife treatment for each patient, the general process is as follows:

  1. Initial consultation: During your consultation, the procedure and its risks and benefits will be explained in detail. If treatment is planned for any area of the body other than the head or spine, it may be necessary to implant small gold markers, called fiducials, into the tumor-bearing region.
  2. Fiducial placement: Fiducials are small (1 mm in diameter, approximately 5 mm long), cylindrical gold markers implanted into soft tissues in or near the tumor (lesion) for the purpose of accurately guiding the CyberKnife radiation beams. Markers are typically required for tumors in the chest, abdomen, pelvis, or other soft tissue that move with respiration, and are not required for tumors in the head or spine. If your treatment requires the placement of fiducial markers, the procedure will be done by a physician or surgeon and will be scheduled for you by the CyberKnife team.
  3. CT scan: Your medical team will use a CT scan to identify the exact size, shape, and location of the tumor and the healthy surrounding tissues to avoid. In some cases, additional radiology studies such as an MRI scan or a PET scan will be used to plan your treatment. Extra scans are fused with the planning CT scan to provide the most detailed, three-dimensional map possible of the area to be treated. (Prior to this step, a light plastic mask—used for brain, head or neck tumors—or a comfortable foam body-immobilizing system—for tumors in the abdomen and pelvis—must be made to help minimize patient movement during treatment. This is a simple and painless process.)
  4. Tumor mapping: Once CT studies are complete, your CyberKnife team will review them in great detail and plan your treatment. Planning considerations include tumor proximity to surrounding organs and structures, as well as tumor location, which influences the direction and number of radiation beams.
  5. Treatment: CyberKnife treatment may be given one to five times, depending on individual needs.
  6. Side effects: Possible side effects vary, and and will be discussed during your consultation. Fatigue may occur a few days after treatment; this improves within two to three weeks. With treatments to the lung, a sore throat may occur; this usually goes away in four to five days. With treatments to the abdomen or pelvis, some patients may experience nausea or diarrhea; if needed, your doctor will prescribe medication to help.
  7. Follow-up: Routine follow-up is important for any recovery. Your team will perform follow-up imaging to monitor the tumor's treatment response. You'll meet with doctors to discuss these image results and map out your next steps of treatment.


CyberKnife provides several advantages over other radiosurgery systems or conventional ways to deliver external radiation:

  • Targets tumors previously considered unreachable by surgery or conventional radiation.
  • May have fewer complications and lower risks than surgery or radiation.
  • Treatment typically completed with less time than traditional treatments in one to five sessions (traditional radiation treatments may require as many as 40 sessions).
  • Does not require anesthesia, incisions, blood loss, or recovery time.
  • Other similar techniques require patients to wear uncomfortable frames during the procedure—CyberKnife uses the body's bony structures or implanted markers to find its target.
  • Outpatient procedure—patients usually go home the same day.
  • Other techniques require patients to hold their breath during treatment—CyberKnife uses the Synchrony Respiratory Tracking System to follow tumor movement even while you breathe.
  • Radiation beamed on the tumor from more than 1,400 different possible angles, allowing concentrated radiation on the tumor itself and avoiding surrounding, healthy tissue.
  • Safe and effective treatment of areas that have received radiation therapy before—not previously possible, and a new option for these patients.
  • Unlike radiosurgery systems, the dose can be spread over multiple visits, particularly helpful for avoiding damage to critical brain tissue and nerves when treating brain tumors.

CyberKnife Clinical Trials

We are running a number of CyberKnife clinical trials:

  • Pancreatic Tumors: Doctors often try to make some pancreatic tumors operable by first shrinking them with chemotherapy and radiation. We’re substituting CyberKnife for conventional radiation to improve results.
  • Liver Tumors: Our initial trial found that CyberKnife treatment of inoperable tumors was as effective as other options: chemoembolization, radio frequency ablation and conventional radiation. It didn’t matter if the tumors originated in the liver or spread (metastasized) from elsewhere.
  • Lung Cancer: Initial results show that CyberKnife is as effective as surgery for patients who are not good candidates for an operation and have early-stage cancer.

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MedStar Georgetown University Hospital
3800 Reservoir Rd., NW
Washington, D.C. 20007