Meningioma
Meningiomas are the most common primary central nervous system tumour and are usually benign, though grade and location determine behaviour. Many are observed rather than treated.
Disease categories
Major disease categories
- Grade 1 meningioma
- Atypical meningioma (grade 2)
- Anaplastic meningioma (grade 3)
- Multiple meningiomas
Molecular
Molecular considerations
NF2 alteration is the most frequent finding. AKT1, SMO, TRAF7, KLF4 and PIK3CA alterations define molecular subgroups that correlate with location. TERT promoter alteration and CDKN2A/B deletion indicate more aggressive behaviour irrespective of histological grade.
Markers commonly discussed in meningioma
- NF2
- AKT1
- SMO
- TRAF7
- TERT promoter
- CDKN2A/B deletion
- Methylation class
Not exhaustive, and not every marker is assessed in every patient. Which of these is relevant depends on the individual case and should be discussed with the treating team.
Testing
Genomic testing considerations
Molecular assessment is increasingly discussed for grading refinement, particularly where histology and behaviour disagree.
Germline
Germline considerations
Neurofibromatosis type 2 is considered where there are multiple meningiomas or a young presentation. Prior cranial radiotherapy is also relevant.
Molecular monitoring
ctDNA and liquid biopsy considerations
Investigational.
Single-cell & computation
Single-cell and algorithmic approaches
Single-cell sequencing in neuro-oncology is used to characterise the cellular hierarchy within a tumour, including the stem-like populations implicated in recurrence, and to describe the immune compartment that bulk profiling represents poorly. Single-cell DNA analysis addresses regional heterogeneity, which is pronounced in glioma. Algorithm work is dominated by DNA methylation classification, which has become one of the more reliable diagnostic tools in difficult central nervous system cases, alongside cerebrospinal fluid analysis methods.
Decisions
Treatment decision questions
Questions worth raising with a treating team when a decision is being made:
- Is the histological grade documented?
- Have TERT promoter and CDKN2A/B status been assessed where behaviour is aggressive?
- Is observation appropriate rather than intervention?
Resistance
Resistance and recurrence questions
- Has the grade been reassessed on recurrence, since it can increase?
Trials
Clinical trial considerations
Grade and molecular subgroup shape the relevant trial set.
When a precision oncology review may help
A review is most useful where the standard pathway has been exhausted or where the picture is more complicated than a protocol accounts for — rare presentations, treatment resistance, complex or apparently contradictory molecular findings, or a decision between several defensible options.
The output is a structured analysis and a set of questions for the treating team. It is not treatment, and it does not replace the treating oncologist.