[Undifferentiated carcinoma of the nose and paranasal sinuses. A clinicopathologic and immunohistochemical study]

A clinico-pathological and immunohistochemical study of 22 cases of undifferentiated carcinoma (UC) of the nose and paranasal sinuses is presented. There were 6 nasal and 16 sinusal lesions. Eleven were small cell, 7 of the intermediate type and 4 of the large cell type. All the large cell UC originated in the sinuses. Immunohistochemically all but three of the UC (all small cell) were positive for an epithelial marker. EMA was better in this study than cytokeratin and CEA (19, 14 and 8 positive cases). Neuroendocrine markers were positive in 5 cases of the large cell UC (Table I). Of the 18 cases with follow up, 3 patients died of their tumor, 9 were alive with disease and 5 were with no evidence of disease after an average of 36 months. Patients with UC of the intermediate variant and large cell type had a better prognosis than those of the small cell type (Table 2). Cases treated with surgery and radiation therapy with or without chemotherapy had a better prognosis than those treated with either one of those treatments alone. This study shows that many of the UC of the nose and sinuses have a neuroendocrine phenotype and although they are aggressive neoplasms they seem to be not as lethal as suggested in the literature.