CyberKnife: Indications And Evidences in India
The CyberKnife Robotic Radiosurgery System is a non-invasive alternative to surgery for the treatment of both cancerous and non-cancerous tumors anywhere in the body, including the prostate, lung, brain, spine, liver, pancreas and kidney. The treatment – which delivers beams of high dose radiation to tumors with extreme accuracy – offers new hope to patients worldwide.
Though its name may conjure images of scalpels and surgery, the CyberKnife treatment involves no cutting. In fact, the CyberKnife System is the world’s first and only robotic radiosurgery system designed to treat tumors throughout the body non-invasively. It provides a pain-free, non-surgical option for patients who have inoperable or surgically complex tumors, or who may be looking for an alternative to surgery. These high dose radiation beams can be given from any angle by precisely concentrating on the tumor while causing minimum damage to the nearby healthy tissue and significant structures such as optic nerve or spinal cord.
Types of Conditions Treated by the CyberKnife Surgery
yberKnife treats intracranial (skull base) benign and malignant tumors, as well as spine tumors and lesions of the cervical, thoracic and lumbar regions.
Some intracranial (head and brain) tumors and lesions that can be treated by CyberKnife are-
- Acoustic neuroma
- Anaplastic astrocytoma
- Arteriovenous malformation (AVM)
- Glioblastoma multiforme
- Glomus jugulare tumor
- Pituitary adenoma
- Trigeminal neuralgia
- Vestibular schwannoma
Some, extracranial (outside of the head and brain) tumors and lesions that can be treated by CyberKnife are-
- Colon cancer
- Hepatocellular carcinoma
- Nasopharyngeal carcinoma
- Non-small cell lung cancer
- Ovarian cancer
- Pancreatic cancer
- Prostate cancer
- Renal cell carcinoma
- Squamous cell carcinoma
- Small-cell lung cancer
- Uterine cancer
- Additionally, CyberKnife is capable of full-body targeting for-
- Thoracic surgery (lung)
- General surgery (liver, pancreas and breast)
- Head and Neck surgery (laryngeal, nasopharyngeal, glossal)
- Urological surgery
Benefits of Cyberknife Surgery
- No incisions
- No recovery time
- Zero or minimal side effects
- Fewer treatments required
- Outpatient procedure
- Reduced risk of complications
- Can treat recurrent tumors
- Comfortable, fast and flexible –
Cyberknife Treatment Procedures
The CyberKnife system uses the combination of a robotics and image guidance to deliver concentrated and accurate beams of radiation to intracranial and extracranial targets, many of which are inoperable with sub- millimeter accuracy. The robotic arm is highly flexible, allowing access to tumors in difficult-to-reach locations.
Step 1: Treatment Setup
A special CT scan (called CT/Simulation) is acquired for every patient, and a MRI, if needed, is also acquired. Your physicians use the scans to identify the size, shape and location of the lesion/tumor along with the surrounding vital structures to be avoided.
Making a Mask or Body Mold
Depending on the need for treatment, a custom soft mask (for head/neck treatments) or body mold is formed and used to help minimize movement during the treatment and ensure your comfort. The process is simple and painless.
The treatment of body (non-head) lesion/tumor using the CyberKnife System requires the implantation of gold seeds referred to as fiducial markers. These fiducial markers require a short outpatient procedure to implant 3-6 seeds in and/or around the tumor. This will enable CyberKnife System to track the tumor throughout the treatment. Lesions in the head and spine do not need this placement.
Step 2: Treatment Planning
Your previously obtained CT and MRI data are sent to the CyberKnife treatment-planning computer where the physicians’ team will use advanced software to customize the radiation beams that the robot will deliver to the tumor or lesion during your treatment. You do not need to be present during this step.
Step 3: Treatment Delivery
You will be asked to lie on the treatment table and will be fitted with the custom mask or body mold made for you earlier during the set-up process. In some cases a mild sedative will be given to you to help you relax, along with any other medication that may be needed during treatment. In some cases anesthesia may be required; this evaluation will be done prior to treatment.
During treatment, you will need to lie still. You may sleep during the procedure. The length of treatment varies depending on the location of your lesion/tumor. The image guidance system periodically compares x-ray images to the CT scan to ensure the radiation is targeted accurately at the tumor.
When your treatment session is completed, our nursing staff will do an assessment. When the nursing assessment has been completed, you will be released to home and may resume normal activity within 24 hours. Your physician will prescribe between 1 to 5 treatments. To maximize your healing, we might insert rest days between the treatment days, depending on the treatment site.
As with any radiosurgery or radiation therapy procedure, your progress is likely to be monitored by follow up exams and imaging.
When is Cyberknife a Suitable Treatment Option?
Radiation therapy, surgery or chemotherapy are some of the traditional therapies that are used in combination with Cyberknife stereotactic radiosurgery. Following are the circumstances that requires Cyberknife system –
When a patient does not want to go through a traditional surgery
When a patient is unable to undergo a surgery
Recurrence of a tumor close to a significant structure like the spine, that previously received maximum dose of radiation
When surgery is not able to remove the entire diseased tissue
When tumor is located near to a significant structure like optic nerves where performing a traditional surgery can increase the risk of damage to these structures
When a surgical procedure is difficult to perform
What is image-guided stereotactic radiosurgery?
The CyberKnife system uses a distinctive radiosurgery device with a linear accelerator (Linac), which produces radiation mounted on a robotic arm. Through the use of image guided cameras, CyberKnife locates the position of the tumor. The Linac attached to the robotic arm is then used to deliver multiple beams of radiation while minimizing exposure to surrounding normal tissue. With sub-millimeter accuracy, CyberKnife is used to treat vascular abnormalities, tumors, functional disorders, and cancers of the body.
Is CyberKnife safe?
CyberKnife, does not present problems associated with traditional surgery. Mainly, there is no anesthesia or anesthesia after effects, the risk of infection and hemorrhaging are minimized. CyberKnife offers accurate precision within sub-millimeter distances and spares healthy tissues surrounding the targeted area.
Through the use of continuous imaging, CyberKnife is able to compensate for patient movement, making uncomfortable head frames obsolete. Also, CyberKnife® uses a robotic arm as a radiation source, enabling many different body parts to be treated. This makes CyberKnife® much more convenient than the gamma knife, or other methods of stereotactic radiosurgery.
After Treatment, when will my tumor or lesion disappear?
The effects of radiosurgery occur gradually and over a period of time. The timeframe can range from days, months or even years depending on the medical condition targeted. Some tumors change slower than others and eventually disappear. Others simply stop growing and present no further cell growth or activity. After treatments patients typically are asked to get periodic images ( CT Scan or MRI) of their tumor(s) so that their physician can monitor the effectiveness of the radiation.
How is a CyberKnife “Radiosurgery” treatment different from a traditional Radiation therapy treatment?
Traditional Radiation therapy typically delivers Radiation to a wide field of tissues in the body resulting in the treatment of both the Tumor and a large amount of surrounding healthy tissues. This is necessary because traditional Radiation therapy systems do not account for Tumor motion and are therefore less accurate. These wide radiation fields often increase the possibility of damaging the normal tissues and increasing the risk of side effects following the radiation treatment. To reduce the number of side effects, clinicians were forced to rethink the way traditional Radiation therapy was delivered. As a result, overall Radiation dose was reduced and number of treatments was divided into 30 – 40 sessions, delivered over a period.
Radiosurgery devices, such as CyberKnife Robotic Radiosurgery System, are designed to deliver Radiation with extreme accuracy, targeting Tumor with minimal damage to the surrounding healthy tissues. The accuracy of the CyberKnife system allows clinicians to deliver very high doses of Radiation safely because the size of the Radiation field is small and includes only the Tumor and a small amount of surrounding tissue. This allows for less damage to surrounding healthy tissue and for clinicians to complete treatment in 1 to 5 days as compared to weeks it takes in traditional radiation therapy.
Through the use of continuous imaging, CyberKnife is able to compensate for patient movement, making uncomfortable head frames obsolete. Also, CyberKnife uses a Robotic arm as a radiation source, enabling many different body parts to be treated. This makes CyberKnife much more convenient than the Gamma Knife, or other methods of Stereotactic Radiosurgery.
How does CyberKnife System differ from other radiosurgery systems?
Unprecedented targeting accuracy Many tumors have proven to move during treatment delivery – even when the patient is immobilized. Using advanced robotic technology and the ability to track tumor motion throughout the treatment, CyberKnife system can deliver radiation with extreme accuracy by automatically correcting tumor movement in real-time. While other technologies rely on static images taken prior to treatment, CyberKnife system automatically tracks, detects, and corrects for even the slightest motion that might occur during treatment delivery.
Unrivaled conformality& dose gradient
Unconstrained by the clockwise / counterclockwise rotations of conventional radiotherapy systems, the robotic mobility of the CyberKnife system enables beams to be delivered from a very wide array of unique angles. By approaching the target from hundreds of different angles, CyberKnife system sculpts delivered dose precisely to the unique contours of the target, while limiting exposure to surrounding critical structures.
Unparalleled healthy tissue sparing
As the only system capable of delivering beams that move real-time with 3D respiratory motion, CyberKnife system significantly reduces treatment margins. With smaller treatment margins, CyberKnife system focuses the prescribed dose to the intended target — not the surrounding healthy tissue.
Can the elderly and children be treated with the CyberKnife?
Since CyberKnife is less risky than traditional surgery it can be a suitable option for the elderly or for pediatric cases. Age is not a crucial factor in excluding patients from CyberKnife treatments. In the case of young children, a pediatrician, anesthesiologist and nurse anesthesiologist may be consulted to ensure the safety and comfort of the child during treatment.
How many times can one receive a CyberKnife treatment?
The frequency of treatments depends on where the tumor is located and what type of tumor is being treated. Most cases receive multi-treatments or can be re-treated with the CyberKnife system.
Is CyberKnife Radiosurgery cost effective?
Cost studies have shown radiosurgery to be less expensive than conventional surgery because it eliminates lengthy post-surgical hospital stays, expensive medication and sometimes months of rehabilitation.