A spontaneous growth of tissue which forms an abnormal mass is called a tumor. A tumor that is noninvasive and noncancerous is referred to as a benign tumor.
Review Date 2/28/2023
Updated by: Jacob Berman, MD, MPH, Clinical Assistant Professor of Medicine, Division of General Internal Medicine, University of Washington School of Medicine, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.