Salivary gland neoplasms: diagnostic approach with focus on patterns of recognition and useful ancillary tools

Salivary gland neoplasms are rare, yet histologically diverse, posing a diagnostic challenge to many practicing pathologists. The current World Health Organization (WHO) 4th edition of head and neck tumors recognizes 31 types of unique salivary gland epithelial neoplasms, including 20 malignant and 11 benign entities. Adopting a systematic diagnostic approach with a focus on patterns of recognition is the key to accurately diagnosing these tumors. Immunohistochemistry and molecular tools can assist in making the correct diagnosis, especially when faced with overlapping morphology. In this review, we explore the utility of various immunohistochemistry and molecular diagnostic tools and outline helpful approaches in diagnosing salivary gland neoplasms.