The CyberKnife is not actually a knife at all. It’s a state-of-the-art piece of equipment that allows specialist oncologists to treat tumours and other medical conditions painlessly without the need for an operation.
CyberKnife uses pencil beams of radiation which can be directed at any part of the body from any direction via a robotic arm. The robotic arm tracks the tumour’s position, detects any movement of the tumour or patient, and automatically corrects its positioning before targeting the tumour with multiple beams of high-energy radiation, destroying abnormal tissue without damaging surrounding areas.
The treatment is so accurate that it’s now possible to treat tumours previously thought to be inoperable. Although the results of treatment do not always show immediately, in most cases the procedure will initially stop the growth of tumours before gradually reducing their size.
As there is no open surgery, the complications normally associated with an operation are eliminated, as is the need for a long recovery time. This makes treatment suitable for those who are not well enough to cope with the side-effects of surgery and most patients leave the clinic the same day as their treatment.
The advanced technology also eliminates the need for patients to be fitted with a brace or restraining device during the treatment phase, making the whole procedure less stressful for patients.
How the CyberKnife works
The vast array of different angles/trajectories from which pencil beams of radiation converge upon the tumour lead to an extremely high cumulative dose of radiation therapy at the convergence point (the target/tumour) and yet a very fast ‘fall-off’ of dose at the periphery of the carefully mapped target. The surrounding normal tissues/organs only receive a small fraction of the high central dose of therapy.
Whilst any tumour may be destroyed by a very high dose of radiation therapy, it has very often been the case, with orthodox radiotherapy, that it has not been possible to deposit the required dose on a tumour without also depositing a toxically high dose of radiation on the surrounding organs. Cyberknife often overcomes this problem by its capability to so accurately target and achieve a fast dose gradient (‘fall-off’) at the perimeter of the tumour/target.
What is the CyberKnife System?
The CyberKnife Robotic Radiosurgery System is a non-invasive alternative to surgery for the treatment of both cancerous and non-cancerous tumours anywhere in the body, including the head, spine, lung, prostate, liver and pancreas. The treatment – which delivers beams of high dose radiation to tumours 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 tumours throughout the body non-invasively. It provides a pain-free, non-surgical option for patients who have inoperable or surgically complex tumours, or who may be looking for an alternative to surgery.
What can the CyberKnife System treat?
The CyberKnife System is a non-invasive alternative to surgery for the treatment of both cancerous and non-cancerous tumours anywhere in the body, including the head, spine, lung, prostate, liver and pancreas. The treatment – which delivers high doses of radiation to tumours with extreme accuracy – offers new hope to patients who have inoperable or surgically complex tumours, or who may be looking for a non-surgical option. To date, more than 50,000 patients have been treated and more than 140 systems are installed worldwide.
Below is a list of some, but not all intracranial (head and brain) tumours and lesions that can be treated by the CyberKnife System:
- Acoustic neuroma
- Arteriovenous malformation (AVM)
- Epidural hematoma
- Vestibular schwannoma
- Anaplastic astrocytoma
- Glioblastoma multiforme
- Glomus jugulare tumorv
- Pituitary adenoma
- Trigeminal neuralgia
Below is a list of some, but not all extracranial (outside of the head and brain) tumors and lesions that can be treated by the CyberKnife System:
- Squamous cell carcinoma
- Small-cell lung cancer
- Hepatocellular carcinoma
- Renal cell carcinoma
- Ovarian cancer
- Arteriovenous malformation (AVM)
- Nasopharyngeal carcinoma
- Non-small cell lung cancer
- Pancreatic cancer
- Prostate cancer
- Colon cancer
- Uterine cancer
How can I find out if a CyberKnife treatment is right for me?
The CyberKnife System has been approved to treat tumours anywhere in the body including the brain, spine, lung, prostate, liver and pancreas. However, if you would like to find out if the CyberKnife System is right for you, talk to your doctor or call us and ask to speak to the Lead CyberKnife Radiotherapist.
How many patients have been treated with the CyberKnife System?
As of July 2018 more than 150,000 patients have been treated worldwide by the CyberKnife System. More than half of those patients were treated with lesions or tumours outside of the brain and head.
What are the patient benefits of treatment with the CyberKnife System?
Patient benefits include:
- No incision
- No anaesthesia
- Little or no recovery time
- No pain
- No hospitalisation
- Immediate return to daily activities
What side effects can I expect after a CyberKnife treatment?
Most patients experience minimal to no short-term side effects and often recover quickly. Depending on the treatment site, some patient’s may experience different side effects such as mild fatigue or nausea. The CyberKnife physician will disclose all possible side effects prior to treatment.
How many times can I receive a CyberKnife treatment?
The frequency of treatments depend on where the tumour is located and what type of tumour is being treated. Most cases can receive multi-treatments or can be re-treated with the CyberKnife System.
After a CyberKnife treatment, when will my tumour or lesion disappear?
The effects of radiosurgery vary and may occur gradually and over time. The timeframe can range from days, months or years depending on the medical condition targeted. Some tumours may disappear slower than others or may simply stop growing and present no further cell activity. After treatment, patients typically are asked to get periodic images (CAT scan or MRI) of their tumour(s) and additional tests may be required, so the physician can monitor the effectiveness of the treatment.
Can the CyberKnife treat paediatric patients?
Yes, but at the moment we are unable to treat children using general anaesthetic. Children – especially younger ones – tend to move around more than adults and this can adversely affect the treatment.
How is a CyberKnife ”radiosurgery” treatment different from a traditional radiation therapy treatment?
Traditional radiation therapy typically delivers radiation to a wide field of tissue in the body resulting in the treatment of both the tumour and a large amount of surrounding healthy tissue. This is necessary because traditional radiation therapy systems did not account for tumour motion and were therefore much less accurate. These wide radiation fields increased the possibility of damage to normal tissue, 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, the overall radiation dose was reduced and the number of treatments was divided into 30 to 40 sessions, delivered over a period of weeks.
Radiosurgery devices, such as the CyberKnife Robotic Radiosurgery System, were designed to deliver radiation with extreme accuracy, targeting the tumour with minimal damage to the surrounding healthy tissue. The accuracy of the CyberKnife System allows clinicians to deliver very high doses of radiation safely because the size of the radiation field is smaller and only includes the tumour 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 vs. the weeks it takes traditional radiation therapy.
How does the CyberKnife System differ from other radiosurgery systems?
- Unprecedented Targeting Accuracy – Many tumours have proven to move during treatment delivery – even when the patient is immobilized. Using advanced robotic technology and the ability to track tumour motion throughout the treatment, the CyberKnife System can deliver radiation with extreme accuracy by automatically correcting for tumour movement in real-time. Where other technologies rely on static images taken just prior to treatment, the CyberKnife System automatically tracks, detects, and corrects for even the slightest motion that might occur throughout treatment delivery.
- Unrivalled Conformality and Dose Gradient – Unconstrained by the clockwise / counter-clockwise 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 directions, the 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 in real-tie with 3D respiratory motion, the CyberKnife System significantly reduces the treatment margins commonplace with other radiation delivery systems. With smaller treatment margins, the CyberKnife System focuses the prescribed dose to the intended target – not the surrounding healthy tissue.
I am currently on or have been on chemotherapy. Am I eligible for a CyberKnife treatment?
The CyberKnife System can treat patients that have either gone through chemotherapy or are currently undergoing chemotherapy. It is important for the patient to provide their physician with a complete medical history, so to the physician can prescribe the appropriate treatment course.
I have had radiation or proton therapy. Am I still eligible for a CyberKnife treatment?
The CyberKnife System can treat patients that have either gone through radiation therapy or are currently undergoing radiation therapy. It is important for the patient to provide their physician with a complete medical history, so the physician can prescribe the appropriate treatment course.
What is the difference between a lesion and a tumour?
A lesion can refer to any focused abnormality in the body, such as a tumour, a blood clot, a cyst, an aneurysm or an inflammatory mass. A tumour is an abnormal collection of cells that has grown due to a change in the cells. Tumours can be either malignant or benign and are a type of lesion.
How is cancer staged and what does this mean?
Staging describes the extent or severity of an individualâ€™s cancer. Knowing the stage of the disease helps the physician plan treatment and estimate prognosis. Staging systems for cancer have evolved over time and continue to change as scientists learn more about cancer. There are many staging systems and some are specific to certain cancer types. The TNM staging system, for example, is used for lung cancer and is based on the extent of the tumour (T), its spread to lymph nodes (N) and its metastasis (spread to other parts of the body) (M). Most cancers can be described as stage 0, stage I, stage II, stage III or stage IV. Physical exams, imaging procedures, laboratory tests, pathology reports, and surgical reports provide information to determine the stage of each cancer.
What are the different treatment options for treating cancer or benign lesions?
The treatment options available vary according to the specific cancer and its location. In general, the treatments can be divided into the following categories:
- Radiosurgery: Radiosurgery, also known as stereotactic radiosurgery, is a form of radiation and despite its name, is not surgery. It is designed to precisely destroy a tumour or lesion by delivering a very high dose of radiation to the tumour in 1 to 5 treatments over a treatment course of 1 to 5 days. Patients are not required to be hospitalized during treatment and the procedure is almost always performed on an outpatient basis.
- Radiation therapy: Radiation therapy is a form of radiation that is usually delivered 5 days a week over a treatment course of 6 to 8 weeks. Radiation therapy, (as opposed to stereotactic radiosurgery), usually treats larger areas that include not only the tumour, but large amounts of healthy tissue, increasing the risk of possible complications. Patients are not required to be hospitalized during treatment and the procedure is almost always performed on an outpatient basis.
- Brachytherapy: Brachytherapy is a specialized form of radiation therapy that requires the surgical placement of small radioactive sources in and around a tumour. The radioactive sources can be implanted either temporarily or permanently, depending on the nature of the source used. Low dose rate brachytherapy (LDR) delivers a prescribed dose over a longer period of time. Radioactive sources are usually implanted permanently. High dose rate brachytherapy (HDR) uses a different source type that delivers dose over a shorter period of time, therefore HDR sources are usually implanted temporarily. Brachytherapy has been used to treat a wide variety of cancers including prostate, breast, lung, head and neck cancers.
- Cryoablation: With Cyroablation, which is also called cryotherapy, a probe is inserted through the skin and into the tumour to freeze the tumour and kill its cells. Placement of the probe requires an incision and can be performed either on an inpatient or outpatient basis depending on the tumour being treated.
- High Intensity Focused Ultrasound (HIFU): HIFU uses a focused ultrasound beam to kill tissue containing cancer cells. It is not FDA approved in the United States, but has been used to treat prostate cancer in Europe.
- Surgery: Surgery or surgical resection is an invasive procedure that requires an incision to remove or cut the tumour out of the body. Surgery can be performed on an inpatient or outpatient basis depending on the tumour being treated. Because of the invasiveness of some types of surgery, some patients may be excluded from receiving this type of treatment.
What is a linear accelerator?
A linear accelerator or LINAC is a device that uses an extremely high voltage power supply to produce high energy radiation.