Neuroendocrine tissues derived from the embryonic neural crest are widely dispersed throughout the body. In mammals, they are in the center of the adrenal gland and are concerned with the synthesis and secretion of the catecholamine hormones (epinephrine and norepinephrine). C-cells in the mammalian thyroid gland also are derived from the neural crest and, during early embryonic development, are incorporated into the last (ultimobranchial) pharyngeal pouch, which subsequently fuses with each thyroid lobe. C-cells are involved in the biosynthesis of calcitonin, a hormone involved in the regulation of calcium homeostasis and skeletal turnover.
Tumors develop occasionally from neuroendocrine cells in the adrenal medulla, thyroid, and aortic and carotid bodies. They are clinically significant due to physical disruption of adjacent normal tissues by the enlarging mass and possibly to autonomous secretion of excess hormone.
Last full review/revision July 2011 by Robert C. Rosenthal, DVM, PhD, DACVIM (Small Animal, Oncology), DACVR (Radiation Oncology)