Benign metastasizing pleomorphic adenoma of salivary gland: Diagnosis of bone lesions by fine‐needle aspiration biopsy

Two cases of benign salivary gland pleomorphic adenomas metastatic to bone (benign‐metastasizing pleomorphic adenomas) diagnosed by fine‐needle aspiration biopsy are presented. Both primary tumors were slightly atypical cytologically but neither case demonstrated features of carcinoma. The metastatic lesions contained benign epithelial, myoepithelial, and stromal components. In both cases the clinical history was either not known by the radiologist or not communicated to the cytopathologist interpreting the case, and a primary tumor of bone was the leading clinical diagnosis. Obtaining pertinent clinical history and comparing the cytomorphology of the bone aspirate with the primary parotid tumor allowed for an accurate diagnosis in both cases. The differential diagnosis with primary bone tumors is discussed and the importance of clinical history is emphasized.