Contributor: Gordon K. Klintworth
Hyperplasia may affect different cell types, such as the fibroblast [hyperplasia - fibroblast] and mast cell [hyperplasia - mast cell]. The hyperplasia may be restricted to specific tissues in the body such as the adrenal gland [hyperplasia - adrenal], bone marrow [hyperplasia - bone marrow], lymphoid tissue [hyperplasia - reactive lymphoid, hyperplasia - reactive polyclonal plasmacytic], parathyroid gland [hyperplasia - parathyroid gland],  prostate gland [hyperplasia - benign prostatic]. Within the adrenal gland the hyperplasia may be limited to the adrenal cortex [hyperplasia - adrenal cortex] or the adrenal medulla [hyperplasia - adrenal medulla]. Within the ocular tissues the embryonic pupillary membrane [hyperplasia - embryonic pupillary membrane], iris [hyperplasia - iris] and retinal pigment epithelium [hyperplasia - retinal pigment epithelium] may become hyperplastic.