BRIEF REPORTS Fine-Needle Aspiration (FNA) and Pleural Fluid Cytology Diagnosis of Benign Metastasizing Pleomorphic Adenoma of the Parotid Gland in the Lung: A Case Report and Review of Literature Yaxia Zhang, M.D., Ph.D., Carmen R. Gomez-Fernandez, M.D., * Merce Jorda, M.D., Ph.D., and Parvin Ganjei-Azar, M.D. Lesions that contain abundant benign myoepithelial cells, including pleomorphic adenomas of salivary gland origin, may present a diagnostic challenge in fine-needle aspiration (FNA) specimens. Benign metastasizing pleomorphic adenoma is a rare neoplasm, in which the benign appearing pleomorphic adenoma, without any histological evidence of malignancy, metastasizes to distant sites including lung. In the absence of clinical history of a pre-existing myoepithelial neoplasm, the presence of myoepi- thelial cells in the lung or any other organs besides salivary glands may create diagnostic difficulty. Here we present the cytologic findings of such a metastatic tumor found in the lung FNA and pleural fluid specimens from a 64-year-old woman, with a history of local recurrent salivary gland pleomorphic adenomas, who presented with multiple bilateral pulmonary nod- ules and pleural effusion. The diagnosis of benign metastasizing pleomorphic adenoma was made based on clinical information and cytomorphology, and confirmed by immunocytochemistry. Diagn. Cytopathol. 2009;37:828–831. ' 2009 Wiley-Liss, Inc. Key Words: fine-needle aspiration; cytology; benign metasta- sizing pleomorphic adenoma; lung; pleural fluid cytology Pleomorphic adenoma, also referred to as benign mixed tumor, is the most common neoplasm affecting the sali- vary glands. Microscopically, the neoplasm is character- ized by both benign epithelial and mesenchymal compo- nents. 1 Rarely, benign-appearing pleomorphic adenomas will metastasize to distant sites including bone, lung, skin, liver and kidney, 2–4 so called benign metastasizing pleo- morphic adenomas. The histologic features of these neo- plasms have been previously described. 5 To the best of our knowledge, this is the first case of benign metastasiz- ing pleomorphic adenoma diagnosed by both FNA and pleural fluid cytology and confirmed with immunocyto- chemistry. Case Reports A 64-year-old woman presented with multiple bilateral pulmonary nodules (Fig. 1) and pleural effusion. She had a history of multiple recurrent pleomorphic adenomas of the left parotid gland. A CT-guided fine-needle aspiration (FNA) biopsy was performed. The pleural fluid was also collected for cytology study. Based on the previous clini- cal history and cytomorphologic findings the diagnosis of a myoepithelial neoplasm consistent with a benign meta- stasizing pleomorphic adenoma was rendered. Using immunocytochemistry, a positive reaction for p63 and a negative reaction for thyroid transcription factor-1 (TTF- 1) further supported the diagnosis. Cytologic Findings Alcohol-fixed smears were stained with routine Papanico- laou stain. The aspirates were cellular and consisted of groups of loosely cohesive plasmacytoid and spindled Department of Pathology, University of Miami Miller School of Medi- cine, Jackson Memorial Hospital, Miami, Florida 33136 *Correspondence to: Carmen R. Gomez-Fernandez, M.D., Associate Professor of Pathology, University of Miami-Jackson Memorial Hospital and UM/Sylvester Comprehensive Cancer Center, 1475 N.W. 12th Ave- nue, Room 2124, Miami, FL 33136. E-mail: cgomez3@med.miami.edu Received 15 November 2009; Accepted 27 April 2009 DOI 10.1002/dc.21123 Published online 6 July 2009 in Wiley InterScience (www.interscience. wiley.com). 828 Diagnostic Cytopathology, Vol 37, No 11 ' 2009 WILEY-LISS, INC.