What are benign and malignant tumors?
No matter where they are located in the body, tumors are classified as benign or malignant. Benign tumors are slow growing, non-cancerous cell masses that have a defined edge and do not spread to other parts of the body. Cells in the tumor are similar to normal cells. Often these tumors can be removed surgically and usually do not recur. Malignant, or cancerous, tumors have cells that look different from normal cells. They can quickly invade surrounding tissue and often have edges that are hard to define, which makes it difficult to remove the entire tumor surgically.
