Salivary gland lesions: recent advances and evolving concepts

Recently, there have been significant developments in our understanding of salivary gland pathology, and new entities, such as mammary analogue secretory carcinoma, have been described. Attempts are being made to identify effective therapeutic agents for salivary duct carcinomas by using molecular diagnostic techniques. Concepts such as high-grade transformation have been described, which not only influence macroscopic and microscopic evaluation of a specimen but, given the high incidence of metastases and morbidity, also carry significant treatment implications. Specific chromosomal translocations, which can be detected by fluorescent in situ hybridization, can augment diagnostic accuracy and carry prognostic implications. The landscape of benign salivary gland lesions is changing with better understanding of chronic sclerosing sialadenitis related to IgG4. This multiorgan inflammatory condition may primarily present as a salivary gland lesion and clinically and radiologically mimic a salivary gland malignancy. Histology and immunohistochemistry play a critical role in its accurate diagnosis. The purpose of this article is to review these changes, with an emphasis on their effect on patient management. Given their diagnostic, prognostic, and therapeutic implications, it is critical that surgeons, oncologists, pathologists, and those involved in caring for patients with salivary gland tumors are aware of these changes while considering management options.