Non-cancerous tumours in the pituitary gland that don't spread beyond the skull.
The pituitary gland is in the skull, below the brain and above the nasal passages. A large tumour can press upon and damage the brain and nerves.
Vision changes or headaches are symptoms. In some cases, hormones can also be affected, interfering with menstrual cycles and causing sexual dysfunction.
Treatments include surgery and medication to block excess hormone production or shrink the tumour. In some cases, radiation may also be used.