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Sinonasal Neuroendocrine Carcinoma Presenting as a Nasopharyngeal Mass

sinonasal cavities are exceedingly uncommon and difficult to diagnose by conventional histologic examination. NEC are small cell neoplasms that show positive immunoreaction to neuroendocrine markers and lack of olfactory maturation.1 The English-language literature consists of small series and isolated case reports, many of which are poorly documented, therefore retrospective analysis of published cases is difficult. In addition, a critical review of these reports indicates that some of the lesions described exhibited clinical or pathological features consistent with other diagnosis, and in particular with olfactory neuroblastoma (ON).2 In this article, we describe a single case of NEC of the sinonasal cavities that clinically presented as a tumor of the nasopharynx.