034 - Serum Chromogranin A and Neuron-Specific Enolase in diagnosis of biologically inactive neuroendocrine tumours

Luca Giovanella, Luca Ceriani, Stefano la Rosa, Silvana Garancini Background. Human Chromogranin A (CgA) is largely distributed in secretory granules of endocrine and neuroendocrine cells. Serum levels of CgA are significantly elevated in neuroendocrine tumours and reflect both secretory activity and tumour burden. Because intense proteolyisis CgA is processed and degraded in tissues and sera: so, total CgA detection is crucial to improve diagnostic accuracy of the marker. Recently a two-site immunoradiometric method has been developed by selecting two monoclonal antibodies against a median, relatively unprocessed, sequence of the molecule. Methods. We selected 32 patients with histologically proved neuroendocrine tumours (NET) without clinical and biological signs of hormonal secretion and evaluated the diagnostic performance of serum CgA and NSE and the relationship between marker’s expression in tissues and in sera. Results. Overall diagnostic accuracy of CgA was better than NSE one. CgA serum levels are related with the extension of the tumour (p