Brain Tumour Surgery vs Radiosurgery: Treatment Options

The choice between brain tumour surgery and radiosurgery turns on time. Surgery removes the tumour immediately; radiosurgery delivers focused radiation without an incision but takes time to work. Surgery is the first choice for most benign tumours, where the aim is complete removal, and the first step for malignant ones. Radiosurgery suits certain small benign tumours and remnants left on a nerve.

Dr. Sonal Gupta, Principal Director & HOD Neuro and Spine Surgery, Fortis Hospital, Shalimar Bagh, New Delhi, India, chooses between these options tumour by tumour, and for a lesion that has already bled she treats the waiting period radiosurgery requires as a risk in its own right. Her decisions turn on three questions: is the tumour benign or malignant, how large is it, and how close does it sit to the parts of the brain that control speech, movement and other vital functions. This article explains each treatment, how she sequences them, and the complication rates she reports. The tumour types themselves are set out in the complete guide to benign and malignant brain tumours.

The four ways to treat a brain tumour

Dr. Gupta describes four treatment modalities for brain tumours:

1. Surgery, to remove the tumour or take a biopsy.
2. Radiotherapy, conventional radiation given over a course of sessions.
3. Chemotherapy, drug treatment that targets dividing cancer cells.
4. Radiosurgery, highly focused radiation aimed precisely at the tumour.

Treatment can use one of these alone or a combination. For malignant tumours, two newer layers now sit on top of the standard options: a genetic study of the tumour and targeted immunotherapy.

Keyhole brain tumour surgery: neuronavigation and the robotic microscope

Open surgery has been the standard form of brain tumour treatment for about a century, and the operating microscope has been part of it for some six decades. The advance, in Dr. Gupta's account, is keyhole microscopic surgery guided by neuronavigation.

Neuronavigation is a computer-assisted system that works like satellite navigation for the brain. The patient's scans are registered to the head in the operating theatre, so the surgeon can see on screen exactly where the instruments are in relation to the tumour. Dr. Gupta uses an advanced computer-assisted neuronavigation machine to locate the tumour during surgery, and it is this precision that makes a keyhole approach possible: a small opening aimed directly at the tumour, rather than a wide exposure to find it.

The robotic microscope is the second technology she relies on. It is a high-end operating microscope that functions as a surgeon-controlled robotic device. In her description, it helps remove the tumour completely without damaging the surrounding brain.

Stereotactic biopsy is the option for tumours that lie deep in the brain. The biopsy is taken through a small hole in the skull, with the needle guided to the target, so that the diagnosis and grade can be established without a full operation.

The cost of these procedures is covered on the craniotomy and brain tumour excision cost page.

Treating benign brain tumours

For a benign, non-cancerous tumour, the primary aim of an operation is to remove the tumour completely. Dr. Gupta adapts the plan to the tumour's size and position:

• Very large tumours may need a two-stage operation: one operation now, and a second two to three months later.
• A small remnant attached to a nerve can be left at surgery and treated afterwards with radiosurgery, rather than risking the nerve.
• Certain small benign tumours can be treated with radiosurgery directly, without an operation.

What is radiosurgery? Gamma Knife, CyberKnife and LINAC

Radiosurgery is a treatment with highly focused radiation, and despite the name it involves no cut. It delivers a high dose of precisely focused radiation to the tumour, usually in a single session or a few sessions, while the surrounding brain receives very little. Dr. Gupta lists three ways to deliver it:

All three serve the same clinical purpose in her practice: treating small benign tumours directly, and treating the fragment of a benign tumour left attached to a nerve after surgery.

Surgery versus radiosurgery: a case in an eloquent area

The trade-off between the two approaches is clearest in a case Dr. Gupta presented. A young woman in her twenties had one episode of bleeding in the brain. She developed paralysis on one side of her body, which improved over time. Her CT scan showed a small lesion located in an eloquent area of the brain.

Eloquent areas are the regions that control critical functions such as movement, sensation, speech and vision. Operating on them is, in Dr. Gupta's words, a bit risky, since damage there can cause lasting deficits. Several doctors had therefore advised the patient to have radiosurgery rather than open surgery.

Dr. Gupta's analysis turned on time. Radiosurgery takes about two years to shrink a lesion of this kind. During those two years, the patient would remain at risk of bleeding again, which she judged a very high risk. Surgery, by contrast, would take away the risk of brain haemorrhage immediately. She offered surgery.

The operation was performed as keyhole surgery under the neuronavigation guided system. It lasted about three hours, and the lesion was completely removed. The case illustrates her central point: radiosurgery avoids an incision, but where the danger lies in the waiting period, a precise operation can be the safer choice even in a high-risk location.

Treating malignant brain tumours

For malignant or cancerous tumours, radiotherapy and chemotherapy are the standard adjuvant treatments, meaning treatments given after surgery to deal with the cancer cells that surgery cannot reach. Because infiltrating cancers such as gliomas always leave microscopic cells behind, surgery alone is rarely the whole treatment.

Dr. Gupta now adds two elements to the standard sequence:

• A genetic study of the tumour, which characterises its molecular make-up. Since the 2021 WHO classification of central nervous system tumours, molecular markers such as IDH mutation and 1p/19q codeletion form part of the diagnosis of gliomas, alongside how the tumour looks under the microscope.
• Targeted immunotherapy, which she describes as the latest advancement in brain tumour treatment, guided by the genetic findings. Immunotherapy for primary brain tumours is still used largely within clinical trials or for tumours with specific molecular targets, so its role is decided case by case.

A suspected high-grade tumour in a child

A referring doctor described a young girl with headache and vomiting over two weeks that had worsened over three days. Her MRI showed a well-defined mass in the left frontal lobe with surrounding swelling and mild midline shift (the brain pushed slightly off centre), and the differential diagnosis lay between a metastasis and a high-grade glioma, a fast-growing tumour of the brain's supporting glial cells. The treating doctors favoured high-grade glioma and had recommended a frontal lobectomy, the removal of the frontal lobe.

Dr. Gupta's answer was that it is not a frontal lobectomy any more. Her approach is neuronavigation-guided surgery directed at the tumour alone, and with a surgical robotic system a near-complete removal of these high-grade tumours can be achieved, which improves the patient's survival. She put complications at less than 5%. The outcome, she explained, depends on the biopsy report and the genetic study; a high-end approach gives extra survival, but she was explicit that she was not saying high-grade tumours can be completely cured.

For treatment after surgery in such a case, standard adjuvant treatment for high-grade glioma is fractionated radiotherapy, usually with temozolomide chemotherapy; stereotactic radiosurgery has no proven role after initial surgery. Further chemotherapy or immunotherapy depends on the biopsy, and the precise plan on the patient's age and the tumour's molecular profile.

Brain metastases: when to operate

For tumours that have spread to the brain from cancer elsewhere, Dr. Gupta advises surgery only in two situations: a single large tumour in the brain, or multiple tumours where one is life-threatening.

Treating brain tumours in children

The operation for a child's brain tumour is the same as for an adult. Radiotherapy and chemotherapy are different: Dr. Gupta stresses that both must be modified according to the child's age. The developing brain is especially vulnerable to radiation, which is why radiotherapy is typically avoided or delayed in very young children where possible. Dr. Arun Singh Danewa covers the oncology side in his guide to childhood solid tumours.

Brain tumour surgery complications and risks

Dr. Gupta reports that post-operative complications of brain tumour surgery have come down to less than 5% of cases. The complications she lists are:

• Epilepsy, seizures arising after the tumour is removed.
• Haematoma, a blood clot at the site where the tumour was removed.
• Infection, a risk of open surgery.
• Incomplete removal, where a very large tumour means part of it has to be left behind.

One referring doctor asked about the space left behind after a tumour is removed. For malignant tumours, Dr. Gupta explains, the surrounding brain is so swollen that the cavity created by removing the tumour fills up in no time, so the void itself is not a concern.

For radiotherapy costs, see the radiation therapy cost page. Symptoms and the diagnostic workup that lead to these decisions are covered in brain tumour headache red flags and when to scan, and Dr. Rahul Gupta's separate masterclass covers the diagnosis and management of brain tumours from another neurosurgeon's perspective. Related conditions are collected on the neuro and spine surgery hub. Referring doctors' questions on specific cases are answered in the Live Discussion with Dr. Sonal Gupta.