This article waslast modified on July 10, 2017.
An increase in the number of cells in an organ, causing enlargement of that organ; this term most often refers to glandular organs, such as the prostate and the adrenal glands. Hyperplasia can produce problems related to a gland's larger size (as in benign prostatic hyperplasia) or excess functioning of the gland (as in adrenal hyperplasia).