Basal cell adenocarcinoma arising from the minor salivary gland in the soft palate: a case report.

Basal cell adenocarcinomas (BCACs) of the oral minor salivary gland are very rare neoplasms. We report on an 86-year-old woman with BCAC arising from the minor salivary gland in the soft palate. Histologically, the tumor was located in the submucosa and showed microinvasion into the adjacent soft tissue without encapsulation. It contained tiny tumor islands with solid and tubular patterns, as well as myxoid stroma. The neoplastic cells were basaloid cells and were composed of large pale cells and small dark cells. They were positive for alpha-smooth muscle actin, cytokeratin 14, and vimentin in the periphery of the tumor island, showing a myoepithelial differentiation. The myxoid stroma was positive for alcian blue and colloidal iron. Apical membranes of the neoplastic cells were positive for MUC1 and CEA. The present case is the 14th documented case of oral BCAC (the fifth case of palatal BCAC).