The revolutionary CyberKnife treatment technology is not new; the CyberKnife System has more than two decades of clinical evidence and has helped millions of patients with various brain tumors and metastases.

The CyberKnife System was approved by the U.S. Food and Drug Administration in 1999 to treat diseases of the head and skull base, including, but not limited to, primary benign and malignant tumors, brain metastases, meningiomas, trigeminal neuralgia, acoustic neuromas, arteriovenous malformations (AVMs), and functional disorders. CyberKnife radiosurgery is even used to treat complex neurosurgical cases, while helping to minimize the dose to healthy brain tissue involved in important functions such as motor control, touch, hearing, and vision.

CyberKnife treatment has been available in Costa Rica since 2019.

CyberKnife System treatment is a non-surgical, outpatient procedure that requires no incisions or general anesthesia. Most patients will not require hospitalization or a lengthy recovery period. This makes CyberKnife treatment an excellent option for patients with medically inoperable lung cancer and those seeking an alternative to surgery.

Radiation therapy is a treatment that uses high-energy X-rays (photons) to kill, shrink, or control the growth of tumors. Radiation therapy works by damaging cells, preventing them from growing and dividing. The goal of any radiation treatment is to destroy cancer cells while minimizing the dose to healthy tissue. As imaging technologies have improved in recent decades, radiation therapy has incorporated these improvements to optimize dose delivery and potentially minimize side effects.

Radiation may be recommended as an alternative to surgery or in addition to other therapies. There are several types of radiation therapy. The CyberKnife System delivers a type of radiation therapy known as stereotactic radiosurgery (SRS).

Stereotactic radiosurgery (SRS) combines highly precise localization with very high doses of extremely accurate radiation delivered externally, maximizing the cell-destroying effect on the tumor(s) while minimizing the dose to nearby organs. The treatment is administered in 1 to 5 sessions in the brain, typically by a team that includes a radiation oncologist and a neurosurgeon. This treatment does not involve surgery.

The precision and accuracy of stereotactic radiosurgery (SRS) delivered with the CyberKnife System can offer several important benefits, including:

• Non-surgical and non-invasive

• Good cancer control

• It can reduce the risk of common cognitive side effects of whole-brain radiation that can affect patients' quality of life, such as remembering things and concentrating.

• Treatments can usually be completed in just 1 to 5 sessions over 1 to 2 weeks

• Most patients can continue with normal activity during and immediately after treatment

• It generally does not require the interruption of chemotherapy cycles or immunotherapy treatments.

• Patients previously treated with whole-brain radiotherapy may be candidates for SRS treatment with CyberKnife

Instead of delivering radiation to all brain tissue, CyberKnife radiosurgery targets the tumor(s) with submillimeter precision; its pinpoint accuracy is within the thickness of a dime, helping to minimize the dose to healthy brain tissue and potentially reducing the risk of common cognitive side effects of whole-brain radiation. Furthermore, CyberKnife radiosurgery can typically be completed in just 1 to 5 sessions over 1 to 2 weeks.

Compared to single-session radiosurgery with frame-based Gamma Knife, treatment with the CyberKnife System can be spread over one to five sessions, which may result in fewer side effects.3 Multi-session radiosurgery with CyberKnife has been shown to allow for safer treatment of tumors near sensitive structures in the head and neck.

Stereotactic radiosurgery (SRS) with the CyberKnife System can offer an alternative to surgical intervention, whole-brain radiotherapy, and conventional fractionation. CyberKnife SRS treatment is frequently used to treat the following types of cases:

1. Brain metastases
When cancer is limited to one (or a small number) of well-defined tumors in the brain, radiosurgery can provide more focused treatment than conventional whole-brain radiation.

2. Radiation-resistant tumors
Some types of brain tumors do not respond well to the low doses of radiation frequently used in conventional whole-brain radiation therapy. However, these radiation-resistant tumors can be effectively treated with high-dose radiation using CyberKnife radiosurgery.

3. Avoid interruption of chemotherapy or immunotherapy
Many patients respond well to multimodal treatment that combines radiotherapy with systemic therapies such as chemotherapy or immunotherapy. Unlike conventional whole-brain radiation, which may require interrupting chemotherapy for several weeks, radiosurgery with CyberKnife can be completed in as few as 1–5 visits and generally does not require interrupting chemotherapy or immunotherapy treatments.

4. Patients with previous brain irradiation
In cases of recurrence, it is generally not possible for patients to undergo a second course of whole-brain radiation. Because CyberKnife radiosurgery delivers precisely targeted radiation, it can provide an effective radiation treatment option for some previously irradiated tumors. Furthermore, clinical data indicate that patients previously treated with CyberKnife radiosurgery (SRS) can be effectively treated with additional courses of SRS—delaying or completely avoiding whole-brain irradiation.¹⁰

5. Reduction of the risk of cognitive decline
In some cases, both whole-brain radiation and targeted radiosurgery may be viable treatment options. Both treatments can provide good long-term cancer control, but patients may choose radiosurgery in an effort to reduce the risk of cognitive side effects affecting memory and concentration.

6. Complicated brain tumors
For tumors and lesions located in close proximity to sensitive structures that affect functions such as motor control, touch, hearing, and vision, the CyberKnife System can provide highly targeted treatment that minimizes the dose to these surrounding sensitive tissues — helping to reduce the risk of short- and long-term impairment.

Treatment with the CyberKnife System is well-tolerated with a low risk of toxicity. Side effects associated with CyberKnife treatment are usually mild and temporary. As with any radiation treatment, side effects can also be severe in some patients and lead to permanent injury or even death. Discuss your specific case with your physician(s) to fully understand the potential risks associated with your treatment. Possible side effects may include, but are not limited to:

• Headache

• Increased intracranial pressure expressed by:

• Nausea

• Vomiting

• Headache

• Orthostatic hypotension

• Seizures

• Edema (which causes headaches)

• Necrosis

CyberKnife treatment can usually be completed in as little as 1-5 sessions over 1-2 weeks.

CyberKnife System treatment is a non-surgical, outpatient procedure that requires no incisions or general anesthesia. Most patients will not require hospitalization or a lengthy recovery period. Most patients can resume normal activities during and immediately after treatment.

No anesthesia is required for CyberKnife treatment and treatment sessions are completed on an outpatient basis.

Most patients can continue with normal activity during and immediately after treatment with CyberKnife.

Most patients can continue with normal activities during and immediately after CyberKnife treatment. Furthermore, CyberKnife radiosurgery targets the tumor(s) with submillimeter precision, helping to minimize the dose to healthy brain tissue and potentially reducing the risk of common cognitive side effects of whole-brain radiation that can affect patients' quality of life, such as memory and concentration.

The robotic design, combined with real-time imaging and automatic synchronization of the radiation beam with skull movement, allows the CyberKnife System to deliver a maximum radiation dose directly to the tumor from virtually any angle with submillimeter precision throughout the entire treatment. This increased precision helps minimize the dose to surrounding healthy tissue, potentially reducing the risk of many common side effects.

When submillimeters matter, even small movements of the skull or the patient can affect the precision and accuracy of treatment. Failure to synchronize radiation dose delivery with skull movement can result in a decreased dose delivered to the target—and an increased dose delivered to surrounding healthy tissue. This can affect the overall effectiveness of treatment and potentially increase the incidence and severity of side effects.

The CyberKnife System continuously tracks, automatically adapts, and synchronizes treatment delivery with the patient's or skull's movement in real time throughout the entire treatment session. This helps ensure that the radiation dose is delivered to the target with submillimeter precision—helping to maximize treatment effectiveness while minimizing the dose to surrounding healthy tissue.

The tissues and structures of the brain are among the most delicate and important for maintaining everything from basic functions to the essential qualities that make patients who they are. Therefore, when it comes to delivering radiation to a target in or near the brain, patients need the most precise approach available. Accurately delivering the prescribed radiation dose to the target site is essential for long-term tumor control—and for helping to minimize the risk of potential side effects that can impact quality of life in both the short and long term.

CyberKnife SRS treatment is a form of hypofractionated radiation therapy. Compared to traditional radiation therapy treatments—commonly called conventional fractionation, which use a relatively lower dose of radiation delivered in a dozen or more sessions over several weeks—hypofractionation involves delivering a higher dose per session (called a fraction) in a smaller total number of sessions. Hypofractionated SRS treatment for brain tumors can typically be completed in as few as 1–5 sessions over 1–2 weeks. Hypofractionated radiation therapy, such as brain SRS, has been shown to provide clinical outcomes as good as conventional fractionation—while dramatically reducing both the number of treatments and the overall cost of care for both patients and payers.

Despite the high dose rate associated with SRS, CyberKnife radiosurgery targets the tumor(s) with submillimeter precision; its pinpoint accuracy is within the thickness of a dime, helping to minimize the dose to healthy brain tissue. Most patients can resume normal activities during and immediately after treatment. However, side effects from radiosurgery or SRS can occur during or after treatment and can be serious.

Extensive clinical research demonstrates that cerebral SRS with the CyberKnife System provides excellent short- and long-term results:

SRS with CyberKnife has been shown to be safe and effective for a wide range of neurological indications including brain tumors3, 10, 14 and spinal tumors4, 5, 15, meningiomas6, acoustic neuromas7, 8, 9, pituitary adenomas16, vascular malformations6 and functional disorders17.

In a clinical study of 133 patients treated for brain tumor metastases who presented with clinical symptoms such as headaches and seizures, 90 percent of patients stabilized or improved their functional status after treatment with the CyberKnife System14.

In a clinical study of 333 patients using the CyberKnife System to treat brain tumor metastases, more than 85 percent of evaluable patients achieved local tumor control two years after treatment.14 That is, the tumor decreased in size or stopped growing.
A clinical study of 199 patients whose injuries were not suitable for treatment with surgery and/or in whom part of the injury remained after surgery found that more than 92 percent of patients experienced stabilization or a significant improvement of their symptoms after treatment with the CyberKnife6 System.

Because it can precisely target tumors, the CyberKnife System can provide an effective radiation treatment option even for some previously irradiated patients. Patients previously treated with SRS using CyberKnife can be effectively treated with additional courses of SRS—delaying or completely avoiding whole-brain radiation.

The CyberKnife System's precise targeting significantly reduces irradiation of surrounding healthy tissue. As a result, the system can provide an effective radiation treatment option for some previously irradiated tumors.

Patients who have previously received whole brain radiation may be able to receive additional SRS treatments with CyberKnife.
Patients previously treated with CyberKnife radiosurgery (SRS) can be effectively treated with additional courses of SRS — delaying or completely avoiding whole brain radiation10.

Not all brain tumors are effectively treated with SRS. Talk to your doctor about your best options and make a decision together.