The biological characteristics of chromogranin A and its role as a circulating marker in neuroendocrine tumours

This paper reviews the biology of chromogranin A (CgA) an CgA-derived pepti des and their possible role as markers for neuroendocrine tumours (NETs). N ETs are neoplasms characterized by a low proliferation rate and, in some ca ses, a favourable prognosis. NETs often overproduce and release biologicall y active substances that are responsible for severe syndromes. The hormones and the biogenic amines released by biologically active NETs are currently used as biomarkers, but there is a need for sensitive markers for those NE Ts that are "biochemically silent". Circulating CgA levels have been demons trated to be augmented in NET patients irrespective of the presence of synd romes related to hormone overproduction. Because of the high sensitivity an d specificity of CgA, this glycoprotein can be successfully used in diagnos is, prognosis and follow-up of NETs. CgA blood evaluation seems of particul ar interest in the management of the gastroenteropancreatic tract NETs and in carcinoids.