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brain tumor

(brayn TOO-mer)
The growth of abnormal cells in the tissues of the brain. Brain tumors can be benign (not cancer) or malignant (cancer).
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Drawing of brain anatomy showing the brain stem, pons, medulla, spinal cord, cerebellum, cerebrum, meninges, ventricles (fluid-filled spaces), and skull.Enlarge this image in new window
Anatomy of the brain, showing the cerebrum, cerebellum, brain stem, and other parts of the brain.
Drawing of the inside of the brain showing ventricles (fluid-filled spaces), choroid plexus, hypothalamus, pineal gland, pituitary gland, optic nerve, brain stem, cerebellum, cerebrum, medulla, pons, and spinal cord.Enlarge this image in new window
Anatomy of the inside of the brain, showing the pineal and pituitary glands, optic nerve, ventricles (with cerebrospinal fluid shown in blue), and other parts of the brain.
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