Explainer | How to spot brain tumour symptoms, their treatment and the promising advances made in the fight against brain cancer
- ‘It’s difficult to determine which brain cancer is the worst,’ an expert says; each type of brain tumour has its own challenges and prognosis
- Brain cancer has no lifestyle causes that can be managed to mitigate risk, but new targeted drugs and CAR T-cell therapy show promise in its treatment
When we received news of my mother-in-law’s brain tumour, we feared the worst.
We were lucky; her tumour, discovered when she was in her late sixties, and which caused a loss of balance, was not cancer.
When the doctor surgically removed it, he described the mass as very hard. This suggested it had been growing for a long time, he said, and drew an analogy with nature – “the older a tree, the harder the wood”.
Surgery fixed her, and she ran out of years before the tumour ever became problematic again.
Brain cancer survivor credits coffee enemas, affirmations, meditation
Dr Maverick Tsang Wai-kong, a specialist in clinical oncology at the Hong Kong Integrated Oncology Centre, says tumours are usually described as benign or malignant (meaning they are cancerous), and are classified according to their grade and stage.
Grades are listed as numbers, and stages as Roman numerals; they can have a value of I to IV. The higher the number, the more advanced the cancer, so at stage III, the cancer is bigger than at stage II and may have spread to surrounding tissues. Stage IV describes the spread – called metastasis – to other organs.
Professor Aya El Helali in the Department of Clinical Oncology at the University of Hong Kong is a specialist in medical oncology and president of The Hong Kong Neuro-Oncology Society.
She has seen first-hand the devastating impact that illness can have on individuals and their families. It is heartbreaking to witness, she says.
Brain cancer comes in many forms, she says; gliomas are one of the most common types of brain tumour in adults. They are malignant tumours that start in glial cells, the supporting cells of the brain and spinal cord.
Chinese team creates tiny robot that could help treat brain aneurysms and tumours
Tsang says gliomas account for nearly 80 per cent of all brain tumours, and notes there are several types, including astrocytomas, oligodendrogliomas and ependymomas. The -oma suffix refers to a “swelling or mass”.
Glioblastoma is the most aggressive type of glioma and accounts for about 50 per cent of all malignant brain tumours. The initial signs and symptoms of glioblastoma are non-specific, Tsang says.
“For example, a patient may report headaches, personality changes, nausea, and symptoms similar to those of a stroke.”
CUP cancer is one of the least survivable cancers – but what is it?
Other signs of a brain tumour could include numbness or paralysis in a part or one side of the body, unsteadiness – which my mother-in-law suffered from – hearing loss, vision changes or seizures.
“It’s difficult to determine which brain cancer is the ‘worst’,” says El Helali, “because each type of brain cancer has its own unique set of challenges and prognosis.”
Glioblastoma is considered to be among the most aggressive and difficult to treat brain cancers, she adds. “It has a high rate of recurrence and a poor prognosis.”
What makes glioblastoma so aggressive is that it develops tentacles that invade other areas of the brain, making it hard to remove completely with surgery. It grows – and grows back – very quickly.
“Despite countless efforts to develop new therapies for glioblastoma over the years, the survival rate remains dismal,” says Tsang.
It has risen a little – where once it was 10 months, with the addition of chemotherapy after initial therapy the median survival time increased to 16 months.
Now the standard treatment will be surgery, followed by radiotherapy, chemotherapy and tumour treating fields (TTF), a low-voltage electric field treatment. Then survival can rise to 21 months.
He used to fight fires, now he fights cancer with new therapy – it’s working
Medulloblastoma is one of the most common primary brain tumours in children, El Helali says. It is a fast-growing tumour that starts in the lower back part of the brain.
While this type of brain cancer can be very serious, it is often more responsive to treatment in children than in adults.
Brain cancer has no known cause that could be managed or mitigated, unlike some other cancers – for example, the risk of lung cancer in smokers can be reduced by them stopping smoking.
There are a very few, and very rare, inherited genetic syndromes that are associated with brain tumours. Although 5 to 10 per cent of people with brain cancers have a family history of brain tumour, the vast majority of cases don’t appear to be because of patients’ genetic make-up.
“It’s important to note that having a risk factor does not necessarily mean that one will develop brain cancer,” El Helali says.
“Currently, there are no specific recommendations for preventing brain cancer.”
Brain cancers are described as secondary when they have spread – metastasised – from a primary cancer site elsewhere in the body, such as the lungs, breast, or colon. Those types of cancer are sometimes avoidable.
There is no screening method to detect a brain tumour; patients usually present with symptoms suggestive of an underlying brain tumour and will undergo investigations to determine the diagnosis.
‘I don’t want to give up’: Hong Kong dad fights cancer for his son’s sake
When she began working in this field, says El Helali, the treatment options were limited.
Recently, exciting treatments have targeted specific genetic mutations associated with brain cancers. For example, drugs such as vorasidenib can target a type of mutation known as IDH frequently found in patients with oligodendroglioma and astrocytoma, forms of glioma.
This has led to improved outcomes and increased survival rates for patients with low-grade IDH-mutant gliomas.
Other mutations are frequently found in diffuse midline gliomas, a type of brain tumour that is particularly aggressive and difficult to treat.
Recent research has identified potential targets for these mutations, with drugs currently in clinical trials. Early results have shown promising outcomes.
The incidence of brain cancer in Hong Kong is similar to that globally; according to Hong Kong’s Hospital Authority, annually there were 240 new cases of, and 115 deaths from, primary brain cancer in the years from 2011 to 2020.
Patients have the same opportunity as those elsewhere to receive standard treatments, El Helali says.
Opening more clinical trials in Hong Kong could provide local patients with more opportunities, she adds.
Advances in radiotherapy have made it possible to treat cancer more effectively and with fewer side effects. Two such advances, El Helali explains, are gamma knife radiosurgery and stereotactic radiotherapy.
Gamma knife radiosurgery uses multiple radiation beams to treat tumours with pinpoint accuracy. Stereotactic radiotherapy uses high-dose radiation to target tumours while minimising damage to surrounding healthy tissue.
These techniques have revolutionised cancer treatment and have helped improve the quality of life for many patients.
Other promising developments in the field include two new papers published on CAR T-cell therapy.
He shed 25kg by diet and exercise, in between beating cancer twice
El Helali says this form of cancer treatment involves modifying a patient’s own immune cells to recognise and attack cancer cells. White blood cells, called T cells, are taken from the patient’s blood, genetically modified in a lab to express chimeric antigen receptors (CARs), and then infused back into the patient.
These CAR T cells can then recognise cancer cells that express the same antigen on their surface and destroy them. This new form of immunotherapy has successfully treated some blood cancers.
While the treatment’s effects may be temporary, the positive response brings a glimmer of hope for tackling glioblastoma.
More research and clinical studies are needed to definitively underscore the effect and role of CAR-T in this form of brain cancer, El Helali says, but these advances are “bringing us closer to a potential cure”.
“We must remain optimistic about the future,” she says. “Focusing on providing the best possible care and support to patients and their families is crucial.”
