Pleomorphic Adenoma with Extensive Squamous and Adipocytic Metaplasia Mimicking as Low Grade Mucoepidermoid Carcinoma on FNAC.

Abstract

Pleomorphic adenoma (PA) is the most common salivary gland tumor, accounting for 54-76% of all salivary gland neoplasms. Extensive squamous metaplasia in PA can be mistaken for malignancy, including low grade mucoepidermoid carcinoma and squamous cell carcinoma. Here, we present an unusual case of PA with extensive squamous metaplasia and keratin cyst formations in a minor salivary gland, and discuss its microscopic features, including the immunohistochemical characteristics, and differential diagnosis of this uncommon presentation.