Translocation-associated salivary gland tumors: a review and update

In recent years the discovery of translocations and the fusion oncogenes that they result in has changed the way diagnoses are made in the salivary gland. These genetic aberrations are recurrent and reproducible and at the very least serve as powerful diagnostic tools in salivary gland diagnosis and salivary gland classification. They also show promise as prognostic markers and hopefully as targets of therapy. Many of these fusions have been found in other tumor types that show little to no overlap with their salivary gland counterparts, but effectively they are specific within the salivary gland. In this review the 5 tumors currently known to harbor translocations will be discussed, namely pleomorphic adenoma, mucoepidermoid carcinoma, adenoid cystic carcinoma, mammary analog secretory carcinoma, and hyalinizing clear cell carcinoma. The discovery and implications of each fusion will be highlighted and how they have helped reshape the current classification of salivary gland tumors.