Basal cell adenoma of maxillary sinus mimicking ameloblastoma.

Basal cell adenoma (BCA) is a rare basaloid tumor, with only 20% of cases occurring in minor salivary glands. Histologically, BCA is characterized by the presence of basaloid cells and may frequently be mistaken with canalicular adenoma, basal cell adenocarcinoma, adenoid cystic carcinoma and basaloid squamous cell carcinoma. Immunohistochemistry may aid in arriving at a final diagnosis as in the present case. Reported here is a case of locally aggressive BCA. Histologically, the lesion mimicked ameloblastoma and other entities which posed a diagnostic challenge. There are no reports of BCA presenting as an aggressive lesion available in English literature so far; moreover, merely a single case of BCA of maxillary sinus has been previously reported to the best of our cognition. This case report highlights the rarity of this tumor with regards to its site of origin, clinical behavior and histopathological mimics.