Primary moderately differentiated neuroendocrine carcinoma (atypical carcinoid) of the larynx: A case report with immunohistochemical and molecular study

On immunohistochemical analysis, the lesion characteristically revealed both neuroendocrine and epithelial differentiation with diffuse staining for chromogranin A, synaptophysin and neuron-specific enolase (NSE) and epithelial membrane antigen (EMA) and overexpression of p53 protein. PCR of NEC DNA did not show any signal for HPV DNA. Thus, this neoplasm is not due to an HPV infection, but a mutation of p53 gene which could cause immunohistochemical overexpression of p53 protein.