Emerging Markers from Molecular Studies: Application into Routine Salivary Gland Fine Needle Aspiration Biopsy Practice

Salivary gland neoplasm (SGN) is one of the largest groups of neoplasms, with over 3 dozen benign and malignant tumors in the 2005 WHO classification and with additional entities recognized during the last decade. Current success of fine needle aspiration biopsy (FNAB) in SGN diagnosis is largely because of its high sensitivity and specificity in: 1) distinguishing neoplastic from non-neoplastic salivary gland lesions and 2) distinguishing benign and low grade salivary gland neoplasms from high grade malignancies. However, precise subtyping of SGNs remains a diagnostic problem for some FNAB cases. These challenging cases include: 1) low grade malignancies with minimal malignant cytological features; 2) accurate subtyping of high grade malignancies, including metastatic malignancies; 3) benign SGNs that can only be differentiated from their malignant counterparts by growth pattern evaluation (e.g. basal cell adenoma vs. basal cell adenocarcinoma).