What is CyberKnife®?
CyberKnife treatment is based on the delivery of radiation on any tumor or sick site in the body with complete accuracy and minimal effect on surrounding healthy tissues. Treating tumors without impairing the body's natural balance, this method is described as "the point shot" in cancer treatment. This method that does not require a surgical procedure constitutes an alternative option to surgery and radiotherapy in many benign and malignant tumors and different diseases. During treatment, several radiation beams are delivered to the target to destroy or stop growth of the tumor or sick site.
How does CyberKnife® function?
CyberKnife® has two important sections: a light source called the linear accelerator and a robotic arm. The radiation source mounted on the robotic arm is capable of delivering radiation on the tumor precisely even with movements of 1 millimeter. Also, by means of the robotic treatment table, the patient’s position can be corrected in 6 dimensions including planar or rotational during the treatment.
The radiation source can stop at approximately 1,200 different points with sensitive movements of the robotic arm during the treatment. Numerous radiations (generally 100 to 150) can be delivered on the tumor or the site of disease according to the characteristics of the treatment planned in advance. The robotic arm brings the radiation source to a different angle each time and directs the radiation on the tumor. In the meantime, imaging cameras mounted around the robotic arm detect the patient’s position. Changes in the patient’s position are perceived by the cameras in real time, and the robotic arm readjusts its position and prevents radiation from being directed to a site other than the tumor. In other words, the radiation source aims at the tumor and cuts off radiation automatically to avoid damage to surrounding tissues even in case of slightest movement of the patient.
When the treatment is completed, the cumulative effect of the radiation delivered on the tumor destroys the tumor or prevents its growth, while sparing the surrounding healthy tissues which receive an insignificant dose.
With CyberKnife® technology, the treatment is performed comfortably both for the patient and the doctor, resulting in faster and more effective outcome.
What are the stages of CyberKnife® treatment?
CyberKnife® treatment is performed by a multidisciplinary team. Patients are evaluated in accordance with medical protocols from various areas of expertise such as radiation oncology, neurosurgery, general surgery, and urology, and treatment eligibility is decided.
Patients who are decided to be eligible for CyberKnife® treatment undergo the following phases. These phases take a few days.
1. Preparation phase
Preparations are made according to the involved body area. If a patient receives brain treatment, a veil-like mask made of plastic material is made to fit the patient's face. Then, tomography and MRI images are obtained. If prostate, pancreas, liver, lung or soft tissue tumors are targeted, 3 to 6 markers are inserted inside the target. A special bed is prepared for the patient to feel comfortable and to reduce patient’s movements.
2. Planning phase
A treatment plan is prepared for targeting radiation on the tumor and sparing the surrounding tissues. At this phase, doctors and medical physicists work in hand on the patient’s radiological images to develop the optimal treatment plan that suits the patient. Thanks to three dimensional, computer-assisted planning and high immobilization, the rate of radiation that healthy tissues are exposed to is minimized.
3. Treatment phase
The treatment session starts when the patient arrives at the CyberKnife® center at the scheduled date and time. The treatment session takes from 1-2 hours and in some cases a patient may need to take 2 - 5 sessions. In such a case, minimum a 24-hour interval is scheduled between two sessions. The patient can return home or work after the treatment session.
Which types of cancer can be treated with CyberKnife®?
With CyberKnife®, tumors of the brain, spine and spinal cord as well as lung, pancreas, prostate, adrenal gland, and some soft tissues, and glomeruli and some functional diseases can be treated.