Synchronous Oncocytic Papillary Cystadenoma and Warthin Tumor of the Parotid Gland.

Warthin tumor (WT) is the second most common benign salivary gland neoplasm. It is also the most frequent salivary gland tumor to occur synchronously or metachronously with another salivary gland neoplasm, in the same gland or on the other side. Oncocytic papillary cystadenomas (OPCs) are rare neoplasms that are more common in minor salivary gland locations and in women. We describe in detail the case of a 73-year-old male smoker with synchronous OPC and WT of the parotid gland. On microscopy, both tumors resembled each other considerably, with the only difference being that the OPC lacked the tumor-associated lymphoid proliferation characteristic of WT. These findings highlight that OPC bears considerable similarity to WT. While this morphological similarity may lead to misdiagnosis on rare occasions, it does not affect patient management, as clinical behavior of both these tumors is similar.