an increase in the size of an organ due to an increase in the numbers of cells The developing embryo increases in size due to cell division The cells of some tissues retain the ability to divide throughout life, like the epithelium and connective tissues but muscle and nerve cells lose their ability to divide soon after birth When hyperplasia is uncontrolled it produces a tumour which may be benign if it is well contained, not destructive and does not spread But it may be malignant, destroys normal tissue, and spread all over the body
A nonmalignant enlargement of the prostate gland commonly occurring in men after the age of 50, and sometimes leading to compression of the urethra and obstruction of the flow of urine