Benign tumors are noncancerous growths in the body. Unlike cancerous tumors, they don’t spread (metastasize) to other parts of the body.Benign tumors can form anywhere. If you discover a lump or mass in your body that can be felt from the outside, you might immediately assume it is cancerous. For instance, women who find lumps in their breasts during self-examinations are often alarmed. However, most breast growths are benign. In fact, many growths throughout the body are benign.Benign growths are extremely common, with 9 out of 10 women showing benign breast tissue changes. Benign bone tumors, similarly, have a higher prevalence than malignant bone tumors. The exact cause of a benign tumor is often unknown. It develops when cells in the body divide and grow at an excessive rate. Typically, the body is able to balance cell growth and division. When old or damaged cells die, they are automatically replaced with new, healthy cells. In the case of tumors, dead cells remain and form a growth known as a tumor.