An abnormal mass of tissue that results from excessive cell division that is uncontrolled and progressive. Tumors perform no useful body function. Tumors can be either benign (not cancer) or malignant (cancer)
Agency for Toxic Substances and Disease Registry, Centers for Disease Control and Prevention, Glossary of Terms, Atlanta, GA, USA 2009. http://www.atsdr.cdc.gov/glossary.html, (Tox - Amer) {788}