The guideline committee has made the following recommendations for research.
Does the addition of concurrent and adjuvant temozolomide to radiotherapy improve overall survival in patients with IDH wildtype grade II glioma?
The World Health Organization (WHO) 2016 reclassification of brain tumours recognised that the molecular characteristics of glioma are extremely important in helping differentiate between disease entities with very different outcomes. Although evidence exists to guide management recommendations for certain molecular gliomas, such as codeleted and non-codeleted grade III glioma, currently no studies have investigated the best approach for the management of grade II glioma with IDH wildtype. The biological behaviour of these tumours is more like a high-grade glioma with a much shorter prognosis than IDH-mutated grade II glioma.
Because of this, some clinicians have advocated treating such tumours with concurrent chemoradiation recommended for grade IV glioma (glioblastoma multiforme, GBM). However, there is currently no research evidence to support this approach and this regimen is more intensive and people experience increased acute and late side effects compared to radiotherapy alone.
Research is needed to establish whether or not this approach is beneficial in terms of improved survival, and at what cost in terms of toxicity and, potentially, reduced quality of life.
To find out why the committee made the research recommendation on managing glioma, see rationale and impact.
Does a dedicated supportive care clinic in addition to standard care improve outcomes for people with low-grade gliomas?
People with low-grade gliomas have significant symptoms and complex healthcare needs across multiple physical, cognitive, emotional and social domains. This is often from the initial diagnosis onwards. There are indications from research literature and patient reports that these needs are currently unmet. Helping people with low-grade gliomas maintain their quality of life and function is important, especially as there is currently no cure, because earlier supportive care interventions and care plans may help reduce unplanned or emergency contact with secondary and tertiary providers.
As no research literature exists which establishes the effectiveness of a specific healthcare intervention, uncertainty exists about the most appropriate intervention to address unmet needs and improve patient-reported outcome measures (or to establish whether current healthcare provision can meet these needs). Current uncertainty is likely to have led to variations in service provision across the UK. It is also possible that no specific intervention is available in some areas.
Research is needed to identify whether, in addition to standard care, a specific supportive care intervention can significantly improve patient-reported outcome measures, and if so to establish what this intervention should consist of.
To find out why the committee made the research recommendation on supportive care clinics for low-grade glioma, see rationale and impact.
Does early referral to palliative care improve outcomes for people with glioblastomas in comparison with standard oncology care?
People with grade IV brain tumours (glioblastomas) have a poor prognosis which has not improved in over a decade. Median overall survival is 14–18 months even with gold-standard chemoradiation following surgery.
From initial diagnosis people experience multiple complex symptoms resulting from neurological impairment. These can significantly impact on their quality of life, function and psychological wellbeing. Their caregivers report high levels of distress and carer burden.
The aim of palliative care is to relieve symptoms and improve people's quality of life and function – not just towards the end of life but throughout the duration of illness. There is some evidence that early palliative care referral significantly improves overall survival, quality of life and mood.
Research in this area is important because this group of people have substantial health needs, which use significant healthcare resources. Supportive care interventions such as early palliative care may improve quality of life and function throughout the duration of illness. It may also help people to manage the distress associated with a reduced life expectancy and participate in advanced care planning.
To find out why the committee made the research recommendation on the early referral to palliative care for glioblastoma, see rationale and impact.
Does early detection of recurrence after treatment improve overall survival/outcomes in molecularly stratified glioma?
Prognosis for brain tumours is inherently uncertain, and recent advances in treatment mean many people with a brain tumour will live for a long time after the initial diagnosis. For these individuals, follow‑up is the longest component of their treatment and it is both expensive for the NHS and (sometimes) a burden for the person. There is no high-quality evidence that follow‑up after treatment is beneficial, no high-quality evidence on the optimal frequency of imaging, and clinical uncertainty about whether such follow‑up is likely to alter outcomes of importance to people with tumours (such as overall life expectancy or quality of life).
Research is needed to establish at what point the value of identifying recurrence early is outweighed by the harms of increasing burden to patients.
To find out why the committee made the research recommendation on the early detection of recurrence after treatment, see rationale and impact.
5 Managing meningioma: immediate versus deferred radiotherapy for incompletely excised grade I meningioma
Is immediate or deferred radiotherapy better for incompletely excised grade I meningioma?
There are no randomised studies on the use of radiotherapy/radiosurgery in the treatment of grade I meningioma. Though case series have shown that people with inoperable and incompletely excised grade I meningioma treated with radiotherapy have high rates of control of their tumour, treatment risks significant side effects. The side effects include: neuropathy, radionecrosis, significant oedema, neuro-cognitive effects, increased risk of stroke and secondary tumours. Therefore the timing of treatment is a balance between control of tumour and side effects. It is not known if early treatment has a greater or lesser chance of long-term tumour control or risk of tumour complications, or if this just risks complications of treatment earlier.
People with grade I meningioma have traditionally been overlooked as a priority area for research. This is likely because of the slow nature of the disease resulting in need for long-term follow‑up and the difficulty to obtain funding for radiotherapy-only studies. However, this lack of research is inequitable, hence the reason for its prioritisation by the committee.
A study on this topic would provide clear information to guide clinicians and people with meningiomas, hopefully leading to overall improvement in quality of life. Because of the slow-growing characteristics of grade I meningioma, treatment decisions made early in the management pathway will have long-term effects on the person with the meningioma's overall quality of life outcomes, and potentially overall survival.
To find out why the committee made the research recommendation on managing meningioma, see rationale and impact.