Cytopathology of papillary oncocytic carcinoma of the thyroid in fine-needle aspiration biopsy

The fine-needle aspirates from two histologically, immunohistochemically, and ultrastructurally confirmed encapsulated papillary oncocytic carcinoma of the thyroid revealed large and small papillary tumor tissue fragments consisting of fibrovascular cores covered with polygonal cells showing abundant and granular cytoplasm and small, oval nuclei. Abundant single and loosely clustered tumor cells with similar cytologic features were also present. Nuclear pleomorphism, irregular nuclear contours, nuclear grooves, and intranuclear cytoplasmic inclusions were not observed in an?, tumor cells. The two patients were alive and well and showed no evidence of armor recurrence and/or metastatic disease 6 and 8 years after their thyroid surgeries, respectively. (C) 2000 Wiley-Liss, Inc.