Immunocytochemical characterization of neuroendocrine tumours of the larynx

Twenty-two neuroendocrine tumours of the larynx were investigated using a panel of immunocytochemical markers. Three were small cell carcinomas, eight were large cell neuroendocrine carcinomas and 11 were paragangliomas. Twenty were positive for protein gene product 9.5, 19 for neuron-specific enolase, 15 for chromogranin A, nine for bombesin, eight for substance P, eight for neuropeptide Y, eight for metenkephalin, seven for somatostatin, five for calcitonin, eight for calcitonin gene-related peptide and one for vasoactive intestinal polypeptide. Bombesin immunoreactivity was largely restricted to the small cell carcinomas and large cell neuroendocrine carcinomas and neuropeptide Y, metenkephalin and substance P to the paragangliomas. This comprehensive immunocytochemical analysis of neuroendocrine tumours of the larynx demonstrates that these tumours represent special entities but have similar patterns of immunostaining to those of neuroendocrine tumours in other sites.