Primary small cell carcinoma of the paranasal sinuses.

An unusual case of small cell carcinoma of the ethmoid sinuses is reported in which electron microscopy confirmed the presence of dense-core granules. The relationship to Pearse's "neuroendocrine programmed" cells is cited. With increasing numbers of different extrapulmonary primary sites for this tumor now being identified, it is believed that these sites must be investigated in any case of suspected small cell carcinoma that cannot be readily attributed to the lung.