Pleomorphic adenoma with extensive mucinous metaplasia mimicking mucoepidermoid carcinoma

Abstract

Background:Pleomorphic adenoma (PA) is the most common benign tumor of the salivary glands. Histologically it is characterized by presenting epithelial as well as mesenchymal elements and may contain various metaplastic changes. Case presentation: In this article, a case of PA with extensive mucinous metaplasia and histologically very similar to mucoepidermoid carcinoma (MEC) is presented. Discussion and Conclusions:Pleomorphic adenoma with extensive mucinous and squamous differentiation can potentially be misdiagnosed as MEC. Immunohistochemistry was not effective in the differential diagnosis and the diagnosis was confirmed by the absence of MAML2 translocation.