Abstract

A congenital salivary gland tumor, sialoblastoma, is extremely rare. A sialoblastoma of the parotid gland, occurring in a 28-week old fetus, is described. The histologic, immunohistochemical, and ultrastructural features of this tumor were studied. The tumor was characterized by solid nests or sheets of tumor cells intermingled with ductal structures lined by a columnar cells. Some of the tumor cells showed squamous differentiation. Immunohistochemically, these epidermoid cells reacted positively with anti-cytokeratin. But anti-S-100, anti- vimentin, anti-smooth muscle actin, anti-GFAP positive cells were not found. The ultrastructure was characterized by primitive epithelial cells. Although various names have been proposed, we favored the term "sialoblastoma". The histogenesis of this tumor is also discussed.

• Keywords: Sialoblastoma;Congenital tumor;Parotid gland