Gamma Knife Radiosurgery in Functional Pituitary Tumours

Q: What conditions can be treated with Gamma Knife?

Gamma Knife is commonly used for: Brain tumors (benign and malignant) Metastatic brain lesions Arteriovenous malformations (AVMs) Trigeminal neuralgia Acoustic neuromas (vestibular schwannomas) Pituitary tumors Certain functional disorders (like tremors)

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Growths from the pituitary gland that emit too many hormones are known as functional pituitary tumours, and they can cause serious clinical symptoms as well as long-term health hazards. For patients with residual, recurring, or medically refractory disease, Gamma Knife radiosurgery (GKRS) has become a very effective, minimally invasive treatment option, even if surgery and medication therapy are still the mainstays of care.

Gamma Knife Radiosurgery in Functional Pituitary Tumours — Functional Pituitary Tumours

The definition of functional pituitary tumours, the procedure of Gamma Knife radiosurgery, and its management role will all be covered in this article.

Functional Pituitary Tumours: What Are They?

The pituitary gland, sometimes referred to as the “master gland,” controls the body’s hormone production. A tumour is referred to as a functional pituitary tumour when it grows in the gland and releases an excessive amount of hormones.

Among the most common kinds are:

Prolactinomas: These tumours release prolactin, which causes erectile dysfunction in men and infertility, galactorrhea, and irregular menstruation in women.
Acromegaly, or growth hormone-secreting tumours, can cause the hands, feet, and jaw to swell and raise the risk of diabetes, high blood pressure, and heart disease.
Weight gain, hypertension, diabetes, and osteoporosis are caused by excessive cortisol production from ACTH-secreting tumours (Cushing’s disease).
Less frequently, TSH or other hormones may be secreted by tumours.

In addition to causing upsetting symptoms, uncontrolled hormone release drastically reduces life expectancy and quality of life.

Standard Methods of Treatment

Typically, treating functioning pituitary tumours consists of:

Transsphenoidal Surgery: Usually the first line of treatment, this procedure aims to remove the tumour and restore normal hormone levels.
Medication: Somatostatin analogues (for acromegaly) or dopamine agonists (for prolactinomas) are examples of medications that may be taken.
Conventional radiotherapy is used in certain situations, but it frequently involves several sessions spread out over several weeks and carries a higher risk of adverse effects.

But not all tumours can be fully removed, and some can return or continue even after treatment with drugs and surgery. Gamma Knife radiosurgery is essential in this situation.

Gamma Knife Radiosurgery: What is it?

The Gamma Knife is a type of stereotactic radiosurgery (SRS) that targets and kills cancer tissue using intensely concentrated gamma radiation beams. There isn’t a real “knife” or incision, despite the term.

Important characteristics include:

Non-invasive: No blood loss, stitches, or wounds.
Precision: Preserves surrounding tissues such as the normal pituitary gland and optic nerves while precisely targeting cancer tissue with sub-millimeter accuracy.
Single session: Patients often receive treatment in a single sitting and are allowed to return home that same day.

Gamma Knife’s Function in Identifying Functional Pituitary Tumours

Radiosurgery using a Gamma Knife is very helpful in:

Tumour that remains after surgery.
Recurring illness that is not improving with medication.
Medical comorbidities render patients unsuitable for surgery.
Patients who favour non-invasive methods of treatment.

Action Mechanism

The Gamma Knife’s radiation causes damage to tumour cells’ DNA, which eventually inhibits their capacity to multiply and generate hormones. In contrast to surgery, the effects take months to years to show up.

Results

Hormonal control: Following treatment, many patients see a normalisation or significant decrease in their hormone levels. Symptoms of Cushing’s disease and acromegaly, for instance, frequently improve significantly over the course of one to three years.
Tumour control: Most series have high local tumour control rates (over 90%).
Improvement of symptoms: Over time, headaches, vision problems, and hormone-related symptoms frequently improve.

Advantages of Gamma Knife

Same-day, outpatient surgery.
No hospitalisation is necessary.
High accuracy lowers the danger to nearby brain areas.
Prevents recurrent cases from requiring multiple procedures.
It can be used in combination with drugs to improve control.

Risks and Adverse Reactions

Despite being usually safe, GKRS has certain hazards.

The most prevalent side effect is delayed hypopituitarism, in which the pituitary’s natural synthesis of hormones gradually declines and needs ongoing hormone replacement.
Radiation effects: If the cancer is very close to important structures, there may be a rare harm to the optic nerves or surrounding brain tissue.
Gradual effect: In contrast to surgery, it could take months or even years to experience symptom relief.

In general, Gamma Knife is thought to be more accurate and safer than traditional radiation.

After-treatment follow-up

Patients need to be regularly checked in with:

Testing for hormone levels (to detect hypopituitarism and check control).
MRI scans (to assess tumour stability or shrinkage).
Consultations in endocrinology (to modify hormone replacement therapy or medicines).

In conclusion

The treatment of functioning pituitary tumours has been completely transformed by Gamma Knife radiosurgery, particularly for patients who have recurring or residual illness. It enhances quality of life, provides long-term hormonal and tumour management, and provides a non-invasive option when medicine or surgery are not enough.

Because of its accuracy, security, and efficiency, the Gamma Knife is still becoming more and more crucial in the treatment of pituitary tumours today.

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FAQ’s

How does Gamma Knife work?

Gamma Knife uses 192–201 precisely focused beams of gamma rays that converge at a single target point in the brain. This high dose of radiation damages the DNA of abnormal cells, stopping their growth or causing them to shrink, while minimizing exposure to nearby healthy tissue.

Is Gamma Knife a surgery?

No, Gamma Knife is not a traditional surgery. It is a non-invasive outpatient procedure performed without any incision, stitches, or general anesthesia in most cases.

What conditions can be treated with Gamma Knife?

Gamma Knife is commonly used for:

Brain tumors (benign and malignant)
Metastatic brain lesions
Arteriovenous malformations (AVMs)
Trigeminal neuralgia
Acoustic neuromas (vestibular schwannomas)
Pituitary tumors
Certain functional disorders (like tremors)

Is Gamma Knife painful?

The procedure is generally painless. Patients may feel mild pressure while the head frame (if used) is applied or may experience slight discomfort from anesthesia injections, but the treatment itself is not painful.

How long does the procedure take?

Depending on the condition and treatment plan, Gamma Knife may take 30 minutes to 3 hours. Most patients go home the same day.

What are the possible side effects?

Common side effects are usually mild and temporary, including:

Headache
Nausea
Fatigue
Mild scalp swelling or tenderness at the frame site
Rarely, some patients may experience delayed radiation effects such as brain swelling or radiation necrosis.

When can the patient return to normal activities after Gamma Knife?

Most patients can return to their normal routine within 24–48 hours after the procedure.
You may feel mild fatigue for a few days.
Follow-up imaging is usually required after 1 year.

How effective is Gamma Knife?

Gamma Knife has a high success rate and has been used worldwide for decades. Its effectiveness depends on the condition treated, size and location of the lesion, and overall patient health. In many cases, it offers results comparable to open surgery with fewer risks.

Can Gamma Knife be repeated if needed?

Yes, in some cases Gamma Knife treatment can be repeated if the disease recurs or if new lesions develop.

Is Gamma Knife safe?

Yes. Gamma Knife is considered one of the safest and most precise forms of radiosurgery, with millions of patients treated globally and extensive clinical data supporting its use.

Who is eligible for Gamma Knife treatment?

Eligibility depends on factors such as:

Size and location of the lesion
Overall health and age
Whether open surgery is too risky
A neurosurgeon and radiation oncologist will decide if Gamma Knife is the best option for you.

What happens before the procedure?

A detailed MRI or CT scan is performed to map the brain.
A lightweight head frame or mask is used for accuracy.
Your doctors plan the radiation dose and target areas using specialized software.

Will I need anesthesia?

Local anesthesia is given if a head frame is used.
General anesthesia is usually not required, except for children or patients unable to remain still.

What is the cost of Gamma Knife in India?

Costs vary depending on hospital, city, and condition treated. On average, Gamma Knife in India ranges from ₹1.5 lakh to ₹4.5 lakh. It is usually more affordable compared to treatment in Western countries. At AIIMS Delhi, it is much more affordable around ₹75,000 which makes it affordable for the patients in need.

Where can I get Gamma Knife treatment in Delhi?

AIIMS Delhi is one of the leading centres for Gamma Knife in India.

AIIMS uses the latest Gamma Knife Perfexion system.

It has successfully treated thousands of patients for brain tumors, blood vessel problems, and even eye cancers.

The treatment is done by expert neurosurgeons such as Dr. Deepak Agrawal and team.

Clinic timings for Gamma Knife OPD at AIIMS Delhi: Monday & Friday, 8:00 AM – 9:00 AM.

Cost is around ₹75,000 and is subsidized compared to private hospitals.

What is the complete process of the Gamma Knife?

The whole procedure is usually done in one day:

Consultation & Planning – Doctors review your scans and decide the treatment.
Head Frame/Mask – A lightweight frame or mask is placed to keep your head still.
Imaging – MRI/CT scans are done to locate the exact target.
Treatment Planning – Specialists plan the dose and direction of radiation.
Gamma Knife Treatment – You lie on the machine; painless radiation beams treat the target (30 mins–3 hrs).
Recovery & Discharge – The frame is removed, and most patients go home the same day.
Follow-up – MRI after a few months to check results.

What formalities do I have to complete prior to getting the date of GK?

Before you get a treatment date, you need to complete a few steps:

OPD Registration – Visit the Neurosurgery OPD (Gamma Knife clinic at AIIMS, Mon & Fri 8–9 AM) and register.
Consultation with Doctor – Meet the neurosurgeon who will check your reports, MRI/CT scans, and medical history.
Investigations – Sometimes fresh MRI/CT or blood tests are needed for treatment planning.
Medical Fitness – Basic checks like blood pressure, sugar, heart condition, etc.

Financial/Insurance Approval –

If using Ayushman Bharat or government schemes, you need approval papers.
If self-paying, you will be given the estimated cost (~₹75,000 at AIIMS).

Consent & Admission Slip – Once doctors confirm you are fit and formalities are done, you sign the consent form.
Treatment Date Allotment – A date is given for your Gamma Knife procedure.

What formalities do I have to complete after getting the date of GK?

Once you receive your Gamma Knife date, you’ll need to do a few simple things before the procedure:

Admission Process – Report to AIIMS on the morning of your procedure and complete admission at the Neurosurgery ward/Daycare.
Paperwork – Carry your OPD slip, MRI/CT films, blood test reports, admission slip, and ID proof. If you are covered under Ayushman Bharat/insurance, keep those approval papers ready.
Consent Forms – You (or a family member) will sign consent for the procedure and anesthesia.
Medical Check-up – Doctors will check your BP, sugar, heart rate, and do a quick physical exam.
Fasting – Usually, you will be asked to not eat or drink for 6 hours before the procedure.
Pre-Procedure Prep – An IV line may be put, and medicines (sedation/antibiotics if needed) are given.
Treatment – You are then taken to the Gamma Knife room for frame/mask placement, imaging, and treatment.

After the procedure, you’ll be observed for a few hours and most patients are discharged the same day or next morning.