Introduction: Small cell neuroendocrine carcinoma (SNEC) of the sinonasal tract is a rare disease.

Objective: Report a descriptive study of a relatively large cohort of SNEC of the nasal cavity and paranasal sinuses.

Method: The medical records of 21 patients presenting with nasal and paranasal SNEC to various French hospitals, from 1989 to 2003, were analysed to determine the clinical features and current treatment of the disease.

Results: Patient data were obtained from eight French hospitals. Twelve of the patients were male and nine were female, with a mean age at presentation of 55 years (range: 27 to 79 years). Patients' staging for nasal cavity malignancy was: T1, four; T2, three; T3, one; T4, 13; N0, 18; N2, three; M0, 20; and M1, one. None of the patients suffered from SNEC of the sinonasal tract with ectopic hormone production. Immunohistochemistry proved useful for diagnosis in 20 cases. Twelve cases were positive for cytokeratin, 14 for chromogranin, eight for neuron-specific enolase and 11 for neuron-specific synaptophysin. One patient had an adenocarcinoma and an inverted papilloma associated with neuroendocrine carcinoma. Patients underwent surgery (11 cases), radiotherapy (14 cases) and chemotherapy (12 cases). Recurrence occurred in 10 cases. Five patients had visceral metastases or cervical lymph node involvement. Nine of the patients died within four years of onset of the disease.

Conclusion: Small cell neuroendocrine carcinoma of the sinonasal tract is an uncommon neoplasm with aggressive clinical behaviour. Recurrence is frequent and the prognosis is poor. However, the current treatment of these neuroendocrine neoplasms varies widely.