Despite diagnostic challenges, the prognosis for brain tumour patients has improved significantly in the last decade, owing to emerging therapies and cutting-edge treatments.
A brain tumour is a growth of cells in the brain or near it. Tumours can occur in or near the brain tissue, and in surrounding locations including the nerves, the pituitary gland, the pineal gland, and the membranes that cover the surface of the brain.
Fortunately, brain tumours are relatively rare. According to World Health Organization's Global Cancer Observatory (GLOBOCAN) 2012 database, only about 2% of all cancers in Malaysia are brain tumours, although the incidence rate has risen over the past few decades. In Singapore, 1,903 cases of brain tumours were reported between 1968 and 2007.
A complex diagnostic challenge
Not all brain tumours are cancerous. A benign or non-cancerous brain tumour may be an abnormal growth which does not invade the surrounding brain tissue or spread to the spinal cord. However, they can exert pressure on vital brain tissue within the skull, potentially causing neurological problems.
Other brain tumours are cancerous and are also known as malignant brain tumours. These tumours occur where the cancer cells invade and spread inside the brain, disrupting healthy brain function even more aggressively than benign tumours, thus destroying brain tissue. A malignant brain tumour may originate from the brain itself, in which case it is called a primary tumour, or has spread to the brain from other parts of the body, known as a metastatic tumour. The exact cause of primary brain tumours remains unknown, but it is thought that certain genetic conditions and previous radiotherapy treatment to the head may increase the risks.
What makes brain tumours unique and particularly challenging to diagnose is that its symptoms can vary depending on the location, size and growth rate of the tumour.
“Early brain tumours tend to present general symptoms such as headaches, fatigue, or dizziness, and mimic other conditions, which makes detecting it challenging. A tumour is usually the last thing a general practitioner (GP) will think of if the patient presents with a headache,” explains Dr Teo Kejia, Senior Consultant Neurosurgeon, Precision Neurosurgery at the Mount Elizabeth Medical Centre, Singapore.
“Usually, the tumour is diagnosed after a seizure, in which case it has already advanced. This is one of the main reasons for delayed diagnosis,” he adds.
Common symptoms of brain tumours include persistent headaches, seizures, changes in vision, memory loss, motor deficits, and cognitive impairment. In some cases, patients may experience personality changes, difficulties in speech and coordination, which can significantly impact their quality of life and daily functioning.
Says Dr Davendran Kanesen, Consultant Neurosurgeon in Sarawak General Hospital, Malaysia, “In many cases, brain tumours are discovered when the healthcare provider performs imaging tests for another medical issue. If a patient is experiencing symptoms indicative of a brain tumour, a neurological examination is typically performed to look for changes to the patient’s balance and coordination, mental status, hearing, vision and reflexes.”
Usually, if a brain tumour is suspected, surgeons or the physicians will advise patients to undergo brain imaging such as a Computed Tomography (CT) Brain, or in some instances a Magnetic Resonance Imaging (MRI) Brain, which provides a detailed view of the brain including the tumour’s size and its precise location and relation to surrounding structures.
“Once the location of the tumour has been confirmed, the neurosurgeon will then ascertain if the tumour is benign or malignant by extracting samples of it, either through surgical excision or a stereotactic biopsy where a small hole is created in the skull to procure tissue samples using a fine needle. Occasionally, a spinal tap, also known as a lumbar puncture is performed to retrieve cerebrospinal fluid samples from around the spinal cord which can then be tested for cancer cells”, Dr Davendran explains.
Unlike cancers originating in other organs, brain tumours are classified based on their cell type, location within the brain, and grade, which is based on how aggressive they are. Brain tumours are classified according to two general categories: (1) low-grade tumours, or Grade 1 and Grade 2 tumours, which are non-cancerous tumours with relatively slower growth rate (2) high-grade brain tumours, or Grade 3 and Grade 4 tumours, which are cancerous and tend to grow and spread aggressively.
An earlier diagnosis can lead to better patient outcomes for many individuals. Detecting the tumour when it is smaller increases the likelihood of achieving a complete surgical resection, which is by far, the only chance of recovery for this type of tumour. Performing surgery on a smaller tumour also reduces the risk of surgical morbidity, thereby improving the overall prognosis and quality of life for the patient.
Cutting-edge treatments improve outcomes for patients
“These days, we recommend a more aggressive treatment of brain tumours to maximise prognosis and best outcomes. Surgery is usually the first option where the patient presents with symptoms such as vomiting, nausea or even drowsiness, caused by the pressure imposed by the increasing size of the tumour,” says Dr Teo.
“Smaller cancerous tumours that we are certain have spread from elsewhere are often treated with a combination of surgery, radiation or chemotherapy. Besides the oncological extent of the disease, we also take into consideration the age and functional status of the patient, i.e., how healthy the patient is to undergo further treatment.”
Cutting-edge procedures such as awake craniotomy or ‘awake brain surgery’, which was initially used in the surgical treatment of epilepsy, is now primarily performed for tumour resection and removal.
Dr Teo explains, “Awake craniotomy is performed on the patient while the patient is awake and is able to communicate with the surgical team. This technique enables the neurosurgeon to remove as much of the tumour as possible while preserving as much of the patient’s neurological function. The operative team plays a crucial role in determining if candidates are sutitable, and if suitable, counselling them through the procedure to ensure they understand what is expected during surgery.”
Leong Pei Ying, a patient of Dr Teo, was first diagnosed with a glioma, 10 years ago. Gliomas are a type of malignant brain tumour affecting about 78% of brain tumour cases. In addition to having a prognosis of 10 months to two years, gliomas tend to recur and patients like Pei Ying will need to undergo surgery periodically to remove the tumour to prevent it from becoming malignant. She has since undergone five surgeries in just 10 years, of which two were awake brain surgeries.
“It took more energy and time to recover from the fourth surgery, the awake brain surgery, compared to the previous surgeries. I was put through a gruelling schedule of daily physiotherapy, occupational therapy, and speech therapy. I had to relearn how to speak, and how to use my left hand and leg. Thankfully this rigorous schedule improved the range of movements in my hand and leg after surgery, and after two months, I was certified fit for discharge,” shares Pei Ying.
After she was discharged, Pei Ying sought out therapists who specialised in neuro-rehabilitation and found a clinic where she underwent rehabilitation three times a week over a year. “Despite my condition and its financial burden, repeated surgery, and often arduous recovery process after each procedure, I have continued to travel all over the world, and pursue my passion for playing the violin,” says Pei Ying, who is now 40.
Other procedures such as Gamma Knife Radiosurgery, are now used as an alternative to chemotherapy and surgery, to treat brain tumours that have metastasised to the brain.
More to be understood and done
Despite the leaps in medical treatments for brain tumours, there are several barriers to treating patients, aside from the disease being difficult to diagnose, often leading to late diagnosis and poor prognosis. These include the costs of undergoing multiple, complex surgeries and the financial burden it imposes on patients.
The costs associated with the diagnosis and treatment of brain tumours can be astronomical, and may vary depending on the type of procedure required, the location, and the severity of the tumour. A study published in the Cancer journal found that globally, brain tumour patients bear the highest indirect costs when compared to patients with other cancers, with expenses totalling US$ 64,790 per year. 'Financial toxicity' is commonly experienced by most cancer patients, especially in brain tumour patients, who are estimated to spend approximately US$268,031 on treatments over the course of five years, post-diagnosis.
Because of the rarity of the disease, in Malaysia, there is a lack of initiatives focusing specifically on brain tumour treatment and research. The National Strategic Plan for Cancer Control Programme (NSPCCP) 2021-2025 addresses cancer prevention and control from a holistic perspective, encompassing primary prevention, screening, early detection, diagnosis, treatment, rehabilitation, palliative care, traditional and complementary medicine, and research. Malaysia also grapples with the lack of access to infrastructure and advanced imaging in rural areas, as specialised medical services are often located in the cities.
Currently in Malaysia, radiosurgery (SRS) and oncological treatments are available for all public hospital patients via a centralised referral basis at the National Cancer Institute (NCI), as well as by their regional/state oncological centres. In some instances, stereotactic radiation therapy (SRT) is also available at their respective healthcare centres, whereas in the private sector, treatment depends on the availability of SRS and oncological services at the respective medical centres.
Dr Davendran elaborates, “The Ministry of Health (MOH) in Malaysia is actively working to bridge the healthcare gaps by enhancing the capabilities of regional hospitals and establishing specialized centres. For example, in Sarawak where I am based, we conduct monthly meetings with a multidisciplinary team of neurosurgeons, histopathologists, neuro-radiologists, and neuro-oncologists, and occasionally with the American Society of Clinical Oncology (ASCO), to discuss complex and challenging cases to outline best possible treatment for our patients located in semi-urban and rural areas.”
As the burden of brain tumours is increasingly being recognised, more investments are being made in areas such as genomics, personalised medicine, and advanced imaging techniques. Stronger collaboration between regional and international research institutions is expected to play a crucial role in developing more novel therapies and improving patient outcomes in the near future. Private-public partnerships within the country must also be strengthened to overcome some of the systemic barriers to access and treatment for brain tumours.
Says Dr Davendran, “Unfortunately, we still do not know what causes brain tumours, and there are no guaranteed ways to prevent them. Certain factors can potentially lower your risk of developing a brain tumour, such as avoiding environmental hazards such as smoking and minimizing exposure to radiation.”
“If you have a close family member who has been diagnosed with a brain tumour, discuss your family history with your doctor, and consider genetic counselling to assess if you carry any inherited risk factors for the disease,” he advises.
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