Meningiomas are a category of primary brain tumour. They are slow growing, and often symptom-free. They form in the meninges - the thin layer of tissues which surround the brain - rather than in the brain itself.

It's estimated that roughly one in a thousand people is affected at some stage in their lives, making meningiomas one of the most common types of brain tumour.

The cause is unknown - although it's been discovered that ionising radiation (x-rays etc) can be a trigger in genetically-prone individuals.

The growth rate appears to be affected by the levels of some hormones, e.g. progesterone. There may also be a link with obesity.

Further reading : American Brain Tumor Association

Also see Glioblastomasplugin-autotooltip__plain plugin-autotooltip_bigGlioblastomas

Glioblastomas are the second most prevalent form of brain cancer (after Meningiomas). The cancers are malignant and highly aggressive, and are hard to treat effectively (either with drugs, surgery of radiotherapy). It's estimated that more than 20,000 cases worldwide occur each year.