Papillary cystic acinic cell carcinoma with many psammoma bodies, so-called psammoma body-rich papillary cystic acinic cell carcinoma: report of a case with fine needle aspiration findings.

Psammoma bodies are infrequent in salivary gland aspirates. We present a case of papillary cystic acinic cell carcinoma with many psammoma bodies and discuss the diagnostic pitfalls with other salivary gland tumors. A 24-year-old woman presented with a 5-month history of a gradually enlarging, painless lump in the left side of the face. Physical examination demonstrated a 2 x 2-cm, nontender, rubbery mass inferior to the auricle in the left parotid area. Sonography showed a 2-cm, cystic mass in the left parotid. Fine needle aspiration was performed and showed mainly papillary clusters and isolated cells with vacuolated cytoplasm and a round nucleus with an inconspicuous nucleolus resembling foamy histiocytes and many psammoma bodies, some of which were surrounded by cells resembling cannonballs. A preliminary diagnosis of papillary cystic salivary gland neoplasm was made and supeficial parotidectomy performed. A diagnosis of papillary cystic acinic cell carcinoma with many psammoma bodies was made. Aspiration cytology of papillary cystic acinic cell carcinoma with many psammoma bodies can be confused with more common tumors, such as cystic mixed tumor and adenoid cystic carcinoma with cannonballs, low grade mucoepidermoid carcinoma or cystic papillary carcinoma of the thyroid.