Synchronous ipsilateral Warthin tumor encased by a separate mucoepidermoid carcinoma of the parotid gland: a case report and review of the literature.

Fine-needle aspiration (FNA) is a cost effective and low morbidity procedure in the initial assessment of salivary gland tumors. However, cytological assessment of ipsilateral synchronous tumors (which make up less than 0.3% of all salivary gland neoplasms) may pose diagnostic challenges. Therefore, a wholesome approach, including FNA with clinical and radiological correlation, is of utmost importance. Here, we report a unique case of Warthin tumor encased by a separate high-grade mucoepidermoid carcinoma that was first diagnosed on FNA. Another striking feature seen was the presence of chronic sialadenitis in the surrounding nonneoplastic salivary gland. The presence of two different neoplasms in the background of chronic sialadenitis raises the question of a possible causal relationship. Traditionally, there has been diagnostic difficulty when dealing with synchronous tumors of the salivary gland and the background of chronic sialadenitis may further complicate the diagnosis. FNA is very helpful and can give important cues to the diagnosis.