"Benign" refers to a condition, tumor, or growth that is not cancerous. This means that it does not spread to other parts of the body. It does not change or destroy nearby tissue. Sometimes, a condition is called benign to suggest it is not dangerous or serious.
In general, a benign tumor grows slowly and is not harmful. However, this is not always the case.
A benign tumor may grow big enough or be found near blood vessels, the brain, nerves, or organs. As a result, it can cause problems without spreading to another part of the body. Sometimes, these problems can be serious.
The opposite of benign is malignant.
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, David R. Eltz, Stephanie Slon, and Nissi Wang.