Small-cell neuroendocrine carcinoma of the nasopharynx: report of a rare case lacking association with Epstein-Barr virus.

Only 2 cases of nasopharyngeal small cell carcinoma have been reported. Another case of this rare type of nasopharyngeal tumor confirmed by immunopositivity for CD56, synaptophysin, and chromogranin A is described in this study. The tumor was also negative for cytokeratin (CK) 20 and thyroid transcription factor-1. Clinical investigation did not find any primary tumor in other anatomic sites. Therefore, this case was established as a primary nasopharyngeal small cell carcinoma. Epstein-Barr virus was shown to be absent by Epstein-Barr virus encoded RNA in situ hybridization study in this case, which further distinguished it from conventional nasopharyngeal carcinoma. Clinical features of this case and 2 previously reported cases are compared. They do not differ from conventional nasopharyngeal carcinoma in clinical presentation, but the prognosis seems to be worse. More cases are needed to confirm the observation and for understanding the clinical behavior of this rare type of nasopharyngeal tumor.