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RGCIRC, Niti Bagh
CyberKnife Treatment in Delhi | Robotic Radiosurgery at RGCIRC
Overview
A cancer diagnosis raises many questions, and for many patients, one of the most significant is whether surgery is the only option. For a growing number of cancers and tumours, it is not. CyberKnife – the world’s first and only fully robotic radiosurgery system – offers a non-invasive, highly precise alternative that delivers targeted radiation directly to a tumour, with sub-millimetre accuracy, while leaving surrounding healthy tissue largely unaffected.
At RGCIRC (Rajiv Gandhi Cancer Institute and Research Centre), CyberKnife treatment is delivered by an experienced team of radiation oncologists and medical physicists as part of a fully integrated, multidisciplinary oncology care pathway. Whether you are exploring treatment options for a newly diagnosed tumour or seeking an alternative for a condition that is difficult to manage surgically, our team is here to assess your suitability and guide you through every step
What is CyberKnife?
CyberKnife is a robotic radiosurgery system that delivers precisely focused beams of high-dose radiation to tumours and abnormal tissue anywhere in the body, without incisions, anaesthesia, or hospitalisation. Despite its name, CyberKnife involves no surgical cutting of any kind. The term “knife” refers to the surgical-grade precision with which radiation is delivered.
The system was developed at Stanford University and has more than two decades of clinical evidence behind it. It combines a lightweight linear accelerator (linac) mounted on a robotic arm with real-time imaging and motion-tracking technology to target tumours with a level of precision that conventional radiation therapy cannot match.
CyberKnife is used to deliver two established forms of high-precision radiotherapy: stereotactic radiosurgery (SRS) for intracranial and spinal targets, and stereotactic body radiation therapy (SBRT) for tumours in the body. Both approaches deliver ablative doses of radiation in a small number of sessions, typically one to five, compared to the weeks of daily treatment that conventional radiotherapy requires.
How Does CyberKnife Work?
Understanding how CyberKnife works helps explain why it is different from other forms of radiation therapy, and why it is suitable for tumours that were previously considered difficult or impossible to treat.
The Robotic Arm
At the core of the CyberKnife system is a six-axis robotic arm that can move freely in all directions around the patient. This arm holds a compact linear accelerator that generates high-energy X-rays. As the arm repositions continuously throughout the treatment session, it delivers radiation from hundreds, sometimes thousands, of unique beam angles, each one precisely aimed at the tumour. Because no single beam carries the full radiation dose, surrounding healthy tissue receives only a small fraction of the total dose, while the tumour receives a concentrated, therapeutically effective amount.
Real-Time Image Guidance
CyberKnife continuously acquires real-time X-ray images throughout treatment and compares them to reference images taken during planning. This allows the system to detect and correct for any change in the tumour’s position, including movement caused by breathing or other involuntary motion, without requiring the patient to hold their breath or be restrained.
Synchrony Motion Tracking
For tumours in areas affected by breathing movement, such as the lung and liver, CyberKnife uses Synchrony, its proprietary real-time motion synchronisation technology. Synchrony tracks the tumour as it moves and continuously adjusts the radiation beam to follow it, maintaining targeting accuracy throughout the session without gating or breath-holding.
Treatment Planning
Before treatment begins, a dedicated treatment planning process is undertaken. This involves high-resolution imaging, typically CT, MRI, or PET-CT, to map the tumour precisely in three dimensions. The radiation oncology team, working with medical physicists, uses this imaging data to design a treatment plan that defines the radiation dose, the beam angles, and the number of sessions required. Treatment is only initiated once the plan has been reviewed and approved.
Conditions and Tumours Treated with CyberKnife
CyberKnife is suitable for a wide range of cancerous and non-cancerous conditions. It is particularly valuable for tumours that are inoperable due to their location or proximity to critical structures, for patients who are not fit for surgery due to age or medical comorbidities, and for tumours that have recurred after previous treatment. The conditions commonly treated with CyberKnife at RGCIRC include the following.
Brain Tumours
CyberKnife treats both primary brain tumours and brain metastases from cancers originating elsewhere. It is used as a primary treatment, as an adjunct to surgery or whole-brain radiation, or for recurrent tumours where repeat conventional radiation would carry unacceptable risk. Conditions include gliomas, meningiomas, acoustic neuromas, pituitary adenomas, and brain metastases from lung, breast, melanoma, and other primaries.
Spine Tumours
The spine presents particular challenges for conventional radiation due to the proximity of the spinal cord. CyberKnife’s sub-millimetre precision makes it suitable for treating both primary spinal tumours and spinal metastases, including in the vertebral body, without exceeding the tolerance dose of the cord.
Lung Tumours
For early-stage non-small cell lung cancer in patients who cannot undergo surgery, CyberKnife SBRT delivers outcomes comparable to surgical resection in eligible patients. Its Synchrony technology is particularly valuable here, tracking tumour movement with each breath cycle throughout treatment.
Prostate Cancer
CyberKnife SBRT for localised prostate cancer allows the full course of treatment to be completed in five sessions rather than the six to eight weeks of conventional radiotherapy, without compromising tumour control rates. It has a well-established evidence base for low- and intermediate-risk prostate cancer.
Liver Tumours
Primary liver tumours and liver metastases from colorectal, breast, and other primaries can be treated with CyberKnife SBRT, particularly where surgical resection or ablation is not feasible due to tumour location, size, or liver function.
Pancreatic Tumours
Pancreatic cancer is among the most challenging malignancies to treat. CyberKnife offers a non-invasive option for locally advanced pancreatic tumours where surgery is not possible, and can be combined with systemic therapy as part of a multimodal approach.
Other Conditions
Beyond oncology, CyberKnife is also used to treat arteriovenous malformations (AVMs) of the brain, abnormal tangles of blood vessels that carry a risk of haemorrhage, and trigeminal neuralgia, a severe facial pain condition that can be refractory to medication. In these applications, it offers a non-invasive alternative to open neurosurgery.
Who is a Candidate for CyberKnife Treatment?
Not every patient or tumour is suitable for CyberKnife. Candidacy is determined through a detailed clinical evaluation by the radiation oncology team, often in the context of a multidisciplinary tumour board review. The following factors generally indicate suitability for CyberKnife treatment. Patients who are typically good candidates include those who:
- Have a tumour that is well-defined on imaging and amenable to precise targeting
- Have early-stage or localised disease where ablative intent is appropriate
- Are not suitable for surgery due to age, medical fitness, or the anatomical location of the tumour
- Have a limited number of metastatic lesions (oligometastatic disease) where ablative treatment of each site is clinically justified
- Have previously received conventional radiation and require retreatment — CyberKnife’s precision reduces the risk of re-irradiating critical structures
- Have tumours in anatomically sensitive locations where conventional radiation would risk unacceptable damage to adjacent critical structures
Patients who may not be suitable include those with very large tumours, diffuse or widely metastatic disease where systemic treatment is the priority, or those with specific anatomical or physiological considerations that preclude accurate targeting. All candidacy decisions are made individually, based on a thorough review of imaging, pathology, and clinical history.
How CyberKnife Differs from Conventional Radiation Therapy
The difference between CyberKnife and conventional radiation therapy is not merely technological. It translates into meaningful clinical outcomes for patients: fewer treatment sessions, less damage to surrounding tissue, greater tolerability, and in many cases, the ability to treat tumours that were previously considered untreatable with radiation.
|
Feature |
CyberKnife (Robotic Radiosurgery) |
Conventional Radiation Therapy |
|
Delivery system |
Robotic arm with six-axis freedom of movement |
Fixed gantry rotating in a single plane |
|
Number of beam angles |
Hundreds to thousands of unique angles |
Typically 5 to 9 beam angles |
|
Treatment sessions |
1 to 5 sessions |
20 to 45 sessions over several weeks |
|
Targeting precision |
Sub-millimetre accuracy with real-time tracking |
Millimetre to centimetre range; no real-time tumour tracking |
|
Motion management |
Synchrony technology tracks and adapts to tumour movement in real time |
Breath-holding or gating techniques; margin added around tumour |
|
Dose per session |
High ablative doses per fraction (hypofractionation) |
Lower doses per fraction spread over many sessions |
|
Anaesthesia required |
No |
No |
|
Hospitalisation |
Not required; outpatient treatment |
Not required for most; outpatient treatment |
|
Invasive frames |
Not required |
Not required |
|
Treatment of moving tumours |
Real-time adaptive tracking |
Limited; margins added to account for movement |
|
Suitable for inoperable tumours |
Yes, including in anatomically challenging locations |
Not always; proximity to critical structures may limit dose |
The practical implications of these differences for patients are as follows. The short course of treatment, typically completed within one to two weeks, means minimal disruption to daily life, work, and other treatment commitments. The precision of delivery reduces the risk of radiation-related side effects in critical adjacent structures. And the ability to treat from multiple angles without rigid immobilisation means the procedure is comfortable throughout.
What to Expect: Before, During, and After Treatment
Before Treatment: Planning and Simulation
The preparation phase begins with a simulation session during which high-resolution imaging is acquired in the treatment position. Depending on the tumour site, this may involve CT, MRI, PET-CT, or a combination. For certain tumours, particularly in the liver, pancreas, or lung, small gold fiducial markers may be placed near the tumour under imaging guidance. These markers serve as reference points that help the CyberKnife system track the tumour’s exact position throughout treatment. The radiation oncology team uses this imaging data to contour the tumour and surrounding critical structures, define the radiation dose prescription, and generate the treatment plan using dedicated planning software. This planning process typically takes several days and involves review by both the radiation oncologist and the medical physicist before treatment is initiated. Patients do not need to restrict their diet or daily activities during this period. Any specific preparatory instructions, such as bladder filling for prostate treatment or fasting for abdominal targets, will be provided by the medical team based on the tumour site.
During Treatment
On each treatment day, patients lie comfortably on the treatment couch in the position established during simulation. The robotic arm moves around the body, delivering radiation from multiple angles. There is no sensation during delivery – patients feel nothing as each beam is administered. Each session typically lasts between 30 and 90 minutes, depending on the complexity of the treatment plan and the number of beam directions required. Patients remain awake throughout and are in continuous communication with the treatment team, who monitor the session from the control room. No anaesthesia, sedation, or immobilisation devices are required. Most patients are able to drive themselves to and from the treatment centre and resume normal daily activities immediately after each session.
After Treatment: Recovery and Follow-Up
One of the advantages of CyberKnife is the absence of a recovery period in the conventional surgical sense. Most patients experience little to no immediate disruption to their daily routine following treatment. Some patients experience mild fatigue in the days following treatment, particularly after sessions targeting the brain or spine. Site-specific reactions — such as mild nausea for abdominal targets, or temporary skin redness over the treated area — may occur but are generally less pronounced than with conventional radiation. The tumour’s response to CyberKnife treatment unfolds over weeks to months. Unlike surgery, where the tumour is physically removed, radiosurgery causes progressive cell death within the treated volume. Follow-up imaging – typically MRI or CT at specified intervals after treatment completion – is used to assess treatment response and monitor for any signs of recurrence.
Possible Side Effects and Complications
CyberKnife is one of the most precisely delivered forms of radiation therapy available, and its side effect profile is generally favourable compared to conventional radiation and surgery. The specific side effects a patient may experience depend on the site being treated, the dose delivered, and individual patient factors. The following provides a general overview.
Common and Typically Temporary Side Effects
- Fatigue, which may develop in the days following each session and usually resolves within one to two weeks
- Mild skin reaction in the area of treatment, typically limited to mild redness or sensitivity
- Nausea or mild discomfort for treatments targeting abdominal or pelvic regions
- Temporary worsening of pre-existing neurological symptoms following brain or spine treatment, as the treated tissue responds to radiation
Site-Specific Considerations
- Brain treatments: A small number of patients experience temporary headache, nausea, or fatigue in the days following treatment. Radiation oedema around the treated area may occasionally develop weeks to months later and is usually manageable with medication
- Lung treatments: Some patients experience mild cough or shortness of breath; in a minority, radiation pneumonitis, inflammation of the lung, may develop and requires medical management
- Prostate treatments: Temporary urinary frequency or urgency is common; bowel changes are less frequent given the precision of targeting
- Spine treatments: Transient worsening of pain at the treated level may occur; radiation myelopathy is rare with appropriately planned treatment
Rare but Serious Complications
Serious complications from CyberKnife treatment are uncommon when treatment is planned and delivered by an experienced team. They may include, depending on the site, radiation necrosis, nerve damage, or secondary effects on adjacent organs. These risks are discussed in detail with each patient during the consent process, and treatment plans are specifically designed to minimise dose to critical structures.
CyberKnife Treatment at RGCIRC
RGCIRC is among a small number of dedicated cancer centres in Delhi to offer CyberKnife as part of a fully integrated radiation oncology programme. For patients evaluating where to receive CyberKnife treatment, the clinical team and institutional infrastructure that support it matter as much as the technology itself. At RGCIRC, we have:
Experienced Radiation Oncology Team
CyberKnife treatment at RGCIRC is planned and delivered by radiation oncologists with specialist expertise in stereotactic radiosurgery and SBRT across a full range of tumour sites. Treatment planning is carried out by dedicated medical physicists using the Accuray Precision Treatment Planning System, ensuring that each plan is optimised for tumour coverage while protecting critical adjacent structures.
Multidisciplinary Review
Every CyberKnife case at RGCIRC is reviewed within the multidisciplinary tumour board before treatment is initiated. This brings together radiation oncologists, surgical oncologists, medical oncologists, radiologists, and pathologists to ensure that CyberKnife is the most appropriate treatment modality for each individual patient, and that it is integrated appropriately within the broader treatment plan where combination approaches are indicated.
Advanced Imaging Infrastructure
Treatment planning at RGCIRC draws on the institute’s full imaging infrastructure, including 3T MRI, Digital PET-CT, and 64-slice CT scanning. Where fiducial marker placement is required, this is carried out by interventional radiologists with specialist experience in image-guided procedures.
Continuity of Care
CyberKnife treatment at RGCIRC is not a standalone procedure. Patients are supported through preparation, treatment, and follow-up by the same clinical team, with structured post-treatment imaging surveillance integrated into the care pathway. For patients receiving CyberKnife as part of a combination treatment approach, care is coordinated across departments to ensure sequencing is optimised.
Accreditation and Quality Standards
RGCIRC holds NABH accreditation (5th Edition) and NABL accreditation for laboratory and diagnostic services – India’s highest standards for hospital and diagnostic quality. The institute’s radiation oncology department operates under established quality assurance protocols for equipment performance, treatment planning, and dose delivery verification.
Book a Consultation at RGCIRC
If you have been advised to consider radiation treatment for a tumour, or if you would like to understand whether CyberKnife is appropriate for your specific diagnosis, our radiation oncology team is available for consultation.
Call +91-11-4702 2222 (Rohini) / +91-11-4582 2222 (Niti Bagh, South Delhi) Book online at care.rgcirc.org | Download the RGCI Care app on iOS and Android OPD Hours: Monday to Saturday, 9:00 AM to 5:00 PM | Emergency Services: 24×7 at both campuses
Frequently Asked Questions (FAQs)
Where can I get CyberKnife treatment near me in Delhi?
RGCIRC offers CyberKnife treatment at its Rohini campus in Delhi as part of its Radiation Oncology Services. To book a consultation with our radiation oncology team, call +91-11-4702 2222 or book online at care.rgcirc.org.
What is the cost of CyberKnife treatment at RGCIRC?
The cost of CyberKnife treatment varies depending on the tumour site, the number of sessions required, and the complexity of the treatment plan. A detailed cost estimate is provided following the initial consultation and treatment planning review. To discuss costs or insurance coverage, please contact our patient services team.
Is CyberKnife treatment painful?
No. Patients feel nothing during CyberKnife treatment. Radiation is invisible and painless. The robotic arm moves around the patient without making contact. Most patients find the procedure comfortable and are able to resume normal activities immediately after each session.
How many sessions are required for CyberKnife therapy?
The number of sessions depends on the tumour site, size, and clinical indication. CyberKnife treatment is typically completed in one to five sessions. Prostate cancer, for example, is commonly treated in five sessions. Brain metastases may be treated in a single session. Your radiation oncologist will specify the number of sessions as part of your treatment plan.
Is CyberKnife safe for brain tumours?
Yes. CyberKnife has an extensive clinical evidence base for the treatment of both primary brain tumours and brain metastases. Its sub-millimetre precision allows high doses to be delivered to the tumour while limiting exposure to surrounding brain tissue. It is used at leading cancer centres worldwide and has been in clinical use for over two decades.
What is the recovery time after CyberKnife treatment?
There is no formal recovery period following CyberKnife treatment. Most patients return to their normal daily routine on the same day as each treatment session. Some patients experience mild fatigue in the days following treatment, particularly for brain or spine targets, but this is generally short-lived. The tumour continues to respond to treatment over weeks to months after the sessions are completed.
Who is eligible for CyberKnife treatment?
Eligibility is determined through a clinical assessment by the radiation oncology team, typically in conjunction with a multidisciplinary tumour board review. CyberKnife is particularly suitable for patients with well-defined, localised tumours who are not candidates for surgery, who have tumours in anatomically sensitive locations, or who require retreatment after previous radiation. Not every tumour or patient is suitable, and candidacy is always assessed individually.
Is hospitalisation required for CyberKnife treatment?
No. CyberKnife treatment is performed on an outpatient basis. Patients attend the treatment centre for each session, which typically lasts 30 to 90 minutes, and return home the same day. No overnight stay is required.
How is CyberKnife different from traditional radiation therapy?
The key differences are precision, treatment duration, and dose delivery. CyberKnife delivers radiation from hundreds of unique angles with sub-millimetre accuracy and real-time tumour tracking, completing treatment in one to five sessions. Conventional radiation therapy typically uses a smaller number of beam angles, delivers lower doses per session over 20 to 45 sessions, and does not track tumour movement in real time. The result is that CyberKnife can deliver higher ablative doses with greater precision and reduced exposure to surrounding healthy tissue.
Can CyberKnife treat cancer without surgery?
Yes. CyberKnife is a non-invasive treatment that requires no incisions, no anaesthesia, and no hospitalisation. For many cancers, including early-stage lung cancer, prostate cancer, brain metastases, and liver tumours, CyberKnife achieves tumour control outcomes comparable to surgery in appropriately selected patients, without the recovery time or surgical risks that open procedures carry.