Test Details: Immunohistochemical testing is carried out on biopsy/resected tissue specimen. This testing helps to identify specific antigens (proteins) within tissue sections utilizing an antigen-specific antibody .Neuron specific enolase (NSE) is a glycolytic enzyme catalysing the reaction pathway between 2-phospho-glycerate and phosphophenol pyruvate playing role in intracellular energy metabolism. NSE has a low specificity to neuroendocrine tumours (“nonspecific enolase”) and is usually used as a screening marker; therefore, the diagnosis must be supported by other more specific markers.