Davina McCall on the brain cyst a routine scan found, and deciding to have it out

Davina McCall's colloid cyst was found by accident. She had been talked into a head-to-toe health scan — she was fit, her blood pressure was low, and she expected, in her words, to ace it. The scan found a benign cyst in the middle of her brain.

She heard the word benign and stopped worrying. It was not cancer, she had probably had it since birth, and she believed she had no symptoms. It took some persuading to get her to have it looked at properly.

A neurosurgeon showed her the picture and named it: a colloid cyst, something that affects around three people in a million, and always in the same place — the third ventricle, in the middle of the brain. That space is finite. Once a cyst fills it, growing any further means causing damage: hydrocephalus, a build-up of fluid on the brain. Very rarely, it can cause sudden death. She was told she might simply not wake up one morning.

What she found hardest was that nobody would tell her what to do. It might grow; it might never grow. She could leave it and watch. She described the feeling of something having taken control of her life, and of being angry at being made to feel in danger every day.

She chose surgery, and chose a surgeon who proposed the larger of two approaches. Part of her reasoning was timing: she was 57, and would rather have the operation while she was otherwise fit than face it in her late sixties, or as an emergency somewhere far from home. She was told the risks included stroke, epilepsy and bleeding. Before the operation she put her will in order and wrote personal letters to her children.

Nothing here is medical advice. A colloid cyst found by chance is not necessarily one that needs treating, and that decision belongs with you and your clinical team.