Senior Consultant Neurosurgeon, Dr Teo Kejia, offers some insights into the complex mysteries of the hidden threat in your brain.

Brain tumours are relatively rare. They are so rare that between 1968 and 2007 there were only about 1.903 cases reported in Singapore, and they did not even make it to the list of top 10 cancers in Singapore.

However, to those who receive this life-altering diagnosis, the illness can be devastating and have potentially deadly consequences. Consultant Neurosurgeon at Precision Neurosurgery, Mount Elizabeth Medical Center, Singapore, Dr Teo Kejia, a specialist in groundbreaking neurosurgical procedures – explains to us how brain tumours occur, what to look out for, and life after prognosis.

ForLife (FL): What is a brain tumour? What are the symptoms, and do they vary according to the location of the tumour?

Dr Teo Kejia (Dr Teo): A brain tumour is a growth of cells in the brain or near it. Brain tumours can happen in or near the brain tissue, on nearby locations include nerves, the pituitary gland, the pineal gland, and the membranes that cover the surface of the brain. A benign (non-cancerous) brain tumour is an abnormal growth in the brain, which does not invade the surrounding brain tissue, or spread to the spinal cord. Non-cancerous brain tumours tend to stay in one place. Malignant brain tumours, on the other hand, can spread and disrupt healthy brain function even more aggressively. Fortunately, brain tumours are relatively rare, with only a small fraction of the population diagnosed each year. Brain tumours can originate from brain tissue itself (known as primary brain tumours) or spread to the brain from other parts of the body (known as metastatic brain tumours). The commonest adult brain tumour was meningioma, followed by Ggliomas (which arise from glial cells).

The symptoms of a brain tumour vary depending on its location. For example, a tumour in the frontal lobe can cause changes in behaviour and difficulty speaking, but a tumour in the occipital lobe may cause visual problems instead, such as blurry vision or even loss of vision in one or both eyes.

More severe symptoms like headaches, nausea, and vomiting often indicate that the tumour, whether primary, metastasized from elsewhere, or a skull base tumour, has grown large enough to raise intracranial pressure. These symptoms serve as important indicators for further evaluation and potential diagnosis. Detecting a tumour in a “sensitive area” of the brain can have benefits by prompting early identification of the tumour.

Unlike many other types of cancer that are more common with increasing age, brain tumours can develop in individuals of any age, from toddlers and very young children to young adults and seniors in their 60s and beyond. The specific types of brain tumours can vary depending on the age group. For instance, older individuals may be more prone to tumours that have metastasized from other parts of the body, which means that certain symptoms associated with brain tumours, such as memory loss, speech difficulties, and problems with balance and coordination, can be mistakenly attributed to ageing. This misinterpretation can delay diagnosis and treatment, allowing the tumour to progress further before being detected.

The prognosis for cancers that have metastasized depends on various factors, including patient’s age and functionality status, the control of the primary cancer and the extent of metastasis. For cancers affecting the brain covering and cerebrospinal fluid pathways, the prognosis is typically very poor. Certain primary brain cancers such as glioblastomas have a prognosis ranging from as little as 10 months to two years, which further underscores the aggressive nature of these tumours and the challenges in treatment and survival outcomes.

Dr Teo Kejia, Consultant Neurosurgeon at Precision Neurosurgery, Mount Elizabeth Medical Center, Singapore

Dr Teo Kejia, Consultant Neurosurgeon at Precision Neurosurgery, Mount Elizabeth Medical Center, Singapore

FL: How often do patients get misdiagnosed when it comes to brain tumours?

Dr Teo: Diagnosing a brain tumour can be challenging. Not every headache is indicative of a tumour. Depending on its location and size, brain tumours can also manifest with a variety of other symptoms besides headaches. They can also be asymptomatic or cause very mild symptoms that are easy to miss.

When a patient presents with a headache for the first time to a general practitioner or family physician, it would typically not be diagnosed as being caused by a brain tumour, given that there are numerous more common causes of headaches, such as migraines. In these cases, the doctor will first manage the symptoms with pain relievers such as paracetamol or etoricoxib, until more concerning symptoms such as vomiting, nausea, or drowsiness develop. With more severe symptoms, further investigation such as magnetic resonance imaging (MRI) and computed tomography (CT) scans may be used to investigate if there is a tumour.

FL: What are some of the more serious symptoms of the disease?

Dr Teo: Symptoms that warrant serious attention include seizures or convulsions, particularly if they occur for the first time in adulthood. Additionally, individuals with brain tumours may exhibit noticeable neurological deficits in vision, hearing, balance, coordination, strength, and reflexes, which can be identified through a comprehensive neurological examination – difficulties observed in these areas can serve as important indicators prompting further investigation by healthcare providers.

Neurocognitive deficits are another common sign to look out for. This is where individuals may notice issues with multitasking, sustaining attention, performing calculations, or making decisions. For instance, someone might struggle to calculate change while shopping for groceries. These subtle cognitive changes, often overlooked or attributed to other factors, could potentially be caused by an underlying brain tumour.

FL: How do you decide on a treatment protocol for a patient when they first come to you?

Dr Teo: Firstly, it’s crucial to determine whether the cancer is primary (originating in the brain) or secondary (having metastasized to the brain from another part of the body). Treatment approaches can vary based on this distinction.

We often treat smaller masses that have spread from elsewhere (metastasized), with a combination of surgery, radiation, chemotherapy; or depending on the molecular markers, with TKIs (tyrosine kinase inhibitors). It is generally a multi-disciplinary approach to the disease, involving the neurosurgeon, neuro oncologist and radiation oncologist. Surgery is often the primary treatment to remove the tumour, followed by adjuvant therapies like post-operative radiotherapy targeting the surgical site.

Primary brain tumours which encompass a variety of types that originate within the brain itself are classified as intra-axial brain tumours, notably gliomas. Others include tumours known as meningiomas, which develop on the brain’s covering. Although typically benign, meningiomas can also be more aggressive, and have a greater risk of recurrence.

As these tumours progress, they often exhibit increased aggressiveness upon recurrence, and neurosurgeons may face limitations in performing multiple surgeries due to concerns over neurological deficits or wound healing issues, sometimes leading to a pessimistic outlook on patient survival.

When a patient presents with a large brain tumour that is causing symptoms of raised intracranial pressure such as vomiting and headaches, surgery becomes urgent, because it becomes a critical race against time to relieve pressure and manage symptoms effectively. Awake brain surgery, also called awake craniotomy, is a type of procedure performed on the brain while the patient is awake and alert. Awake brain surgery is used to treat some brain (neurological) conditions, including some brain tumours or epileptic seizures.

There are also tumours such as schwannomas that grow on nerves associated with our eyes and ears. When left untreated, schwannomas can lead to various problems, such as hearing loss if the tumour is affecting the auditory nerve. Treatment for schwannomas commonly involves surgery, although non-surgical approaches such Gamma Knife radiosurgery can also be considered.

FL: What is awake brain surgery and what does it entail?

Dr Teo:  Awake brain surgery is a ground-breaking technique performed with the patient still being awake during the procedure, and is one of my specialties. This might sound scary, but conducting surgery while the patient is awake or conscious, enables us to map their neuro-cognitive functions, which aids in the removal of as much of the tumour as possible, while safeguarding essential brain functions. The brain’s surface contains numerous functional areas interconnected by white matter tracts that often intersect. Brain tumours can affect these areas and tracts, either displacing them or infiltrating them, complicating tumour removal. Awake surgery enables the surgeon to identify safe pathways on the brain’s surface to access and remove the tumour while minimizing damage to these vital tracts.

During the procedure, the patient will be asked to perform specific tasks. These tasks are not random, but are specifically tailored to locate the tumour’s location and the affected brain areas or tracts. These tasks may include simple movements, language exercises like naming or forming sentences, motor function tests, assessments of executive function, spatial awareness tests, and even emotion recognition. These tasks target higher cognitive functions, which are carefully preserved during the surgery.

The success of the patient completing each task while being operated on helps the surgeon to avoid damaging critical brain regions while removing the tumour, which is how this type of surgery has helped improve the lives of the patients, post-surgery.

FL: Are brain tumours a death sentence?

Dr T: In the past, brain tumours would mean a death sentence for many people, in terms of how aggressive the tumour is and how quickly it would grow. There were also challenges of preserving quality of life post-surgery, which sometimes involved removing significant healthy brain tissue along with the tumour, further impacting patients’ functionality and their sense of self. However, with the remarkable advancements in technology, patients now have the opportunity to lead long, fulfilling, and healthy lives following surgery, free from concerns about losing their cognitive abilities or normal functioning.

Technological innovations like awake brain surgery and Gamma Knife radiosurgery are revolutionizing neurosurgical treatments, offering hope and transformative outcomes for patients with brain tumours. Increased public awareness about these lifesaving options will further empower patients to make informed decisions about their condition, and give the patients the ability to explore multiple approaches to manage their tumours effectively.


Featured image by Dreamstime.
Dr Teo Kejia photo courtesy of Dr Teo Kejia.