PAPIllARy HyPERPlAsTIC NODulE: PITfAll IN THE CyTOPATHOlOgIC DIAgNOsIs Of PAPIllARy THyROID CARCINOmA

Objective: To identify the pitfalls of overdiagnosing papillary formation as papillary thyroid carcinoma (PTC) in thyroid cytology specimens.Methods: Patients with papillary hyperplastic nodules who had preoperative fine-needle aspiration biopsy (FNAB) were selected for this study. All patients had been diagnosed as having either PTC or lesions suggestive of PTC on preoperative FNAB. Pathology reports, surgical reports, and cytopathology slides were reviewed and analyzed for demographic data, nature of surgery, and pathologic features.Results: Six women and 2 men with a mean age of 49 years (range, 16-79 years) were included. The lesion size ranged from 1.0 to 3.5 cm. Four patients were diagnosed as having PTC and 4 as having lesions suspicious for PTC. FNAB specimens were available for review in 6 cases. Surgical pathology slides were reviewed in all cases. When cytologic material was evaluated for the morphologic features that led to the misdiagnosis of PTC by comparing it with FNAB specimens of classic...