A tumor that grows locally but does not spread to other parts of the body. Benign tumors can cause problems because of their spread, as they press and displace normal tisues. They can be dangerous in confined places such as the skull.
Although the cells in a benign tumor are not normal, a benign tumor poses no immediate threat to the patient. However, in some cases a benign tumor may undergo further changes and may become a life-threatening aggressive tumor.
Benign tumors are not cancerous, ie do not spread to other areas of the body. However, their growth and enlargement can cause symptoms by compressing nearby tissue or structures such as nerves. Over time some benign tumors may become malignant.