Objective: The importance of identifying papillary carcinoma or lymphoma amidst background Hashimoto’s/lymphocytic thyroiditis (H/LT) is well documented. However, avoidance of overdiagnosing neoplasms on thyroid fine-needle aspiration (FNA) with only H/LT has not been adequately addressed. Study Design: This study aimed to identify cytomorphologic features leading to overdiagnosing neoplasms within background H/LT. Nine thyroid FNAs classified as suspicious or positive for neoplasm with subsequent thyroidectomy specimens having only H/LT were identified. Cytologic features of these cases were compared to 8 control cases from the same time period and FNAs from both groups were reevaluated for features from the cytology literature. Results: Features leading to overdiagnosing papillary carcinoma were: powdery chromatin, occasional nuclear grooves or holes, and paucity of background lymphocytes. One feature differentiating H/LT from neoplasm noted in most cases was lymphocytes infiltrating follicular groups. In contrast, true papillary carcinomas displayed characteristic features in multiple cell clusters. These clusters were devoid of infiltrating lymphocytes or displayed only rare lymphocytes at their periphery. A microfollicular pattern with paucity of background lymphocytes was the major pitfall in overdiagnosing follicular neoplasm. Conclusions: Features suspicious for neoplasm are often seen in FNA of H/LT, leading to unnecessary surgery. Recognizing this pitfall and its differentiating features should avert overdiagnosis.

Haberal AN, Toru S, Ozen O, Arat Z, Bilezikci B: Diagnostic pitfalls in the evaluation of fine needle aspiration cytology of the thyroid: correlation with histopathology in 260 cases. Cytopathology 2009;20:103–108.
MacDonald L, Yazdi HM: Fine needle aspiration biopsy of Hashimoto’s thyroiditis. Sources of diagnostic error. Acta Cytol 1999;43:400–406.
Bhatia A, Rajwanshi A, Dash RJ, Mittal BR, Saxena AK: Lymphocytic thyroiditis – is cytological grading significant? A correlation of grades with clinical, biochemical, ultrasonographic and radionuclide parameters. Cytojournal 2007;4:10.
Carson HJ, Castelli MJ, Gattuso P: Incidence of neoplasia in Hashimoto’s thyroiditis: a fine-needle aspiration study. Diagn Cytopathol 1996;14:38–42.
Nguyen GK, Ginsberg J, Crockford PM, Villanueva RR: Hashimoto’s thyroiditis: cytodiagnostic accuracy and pitfalls. Diagn Cytopathol 1997;16:531–536.
Kini SR, Miller JM, Hamburger JI: Problems in the cytologic diagnosis of the ‘cold’ thyroid nodule in patients with lymphocytic thyroiditis. Acta Cytol 1981;25:506–512.
Ohmori N, Miyakawa M, Ohmori K, Takano K: Ultrasonographic findings of papillary thyroid carcinoma with Hashimoto’s thyroiditis. Intern Med 2007;46:547–550.
Ravinsky E, Safneck JR: Differentiation of Hashimoto’s thyroiditis from thyroid neoplasms in fine needle aspirates. Acta Cytol 1988;32:854–861.
Liu LH, Bakhos R, Wojcik EM: Concomitant papillary thyroid carcinoma and Hashimoto’s thyroiditis. Semin Diagn Pathol 2001;18:99–103.
Albores-Saavedra J, Wu J: The many faces and mimics of papillary thyroid carcinoma. Endocr Pathol 2006;17:1–18.
Punthakee X, Palme CE, Franklin JH, Zhang I, Freeman JL, Bedard YC: Fine-needle aspiration biopsy findings suspicious for papillary thyroid carcinoma: a review of cytopathological criteria. Laryngoscope 2005;115:433–436.
Szporn AH, Yuan S, Wu M, Burstein DE: Cellular swirls in fine needle aspirates of papillary thyroid carcinoma: a new diagnostic criterion. Mod Pathol 2006;19:1470–1473.
Amrikachi M, Ramzy I, Rubenfeld S, Wheeler TM: Accuracy of fine-needle aspiration of thyroid. Arch Pathol Lab Med 2001;125:484–488.
Raparia K, Min SK, Mody DR, Anton R, Amrikachi M: Clinical outcomes for ‘suspicious’ category in thyroid fine-needle aspiration biopsy: patient’s sex and nodule size are possible predictors of malignancy. Arch Pathol Lab Med 2009;133:787–790.
Ali CZ, Cibas ES: The Bethesda System for Reporting Thyroid Cytopathology. New York, Springer, 2010.
Zeppa P, Cozzolino I, Peluso AL, Troncone G, Lucariello A, Picardi M, Carella C, Pane F, Vetrani A, Palombini L: Cytologic, flow cytometry, and molecular assessment of lymphoid infiltrate in fine-needle cytology samples of Hashimoto thyroiditis. Cancer Cytopathol 2009;117:174–184.
Jogai S, Al-Jassar A, Temmim L, Dey P, Adesina AO, Amanguno HG: Fine needle aspiration cytology of the thyroid: a cytohistologic study with evaluation of discordant cases. Acta Cytol 2005;49:483–488.
Bongiovanni M, Triponez F, McKee TA, Kumar N, Matthes T, Meyer P: Fine-needle aspiration of the diffuse sclerosing variant of papillary thyroid carcinoma masked by florid lymphocytic thyroiditis; a potential pitfall: a case report and review of the literature. Diagn Cytopathol 2009;37:671–675.
Rhoden KJ, Unger K, Salvatore G, Yilmaz Y, Vovk V, Chiappetta G, Qumsiyeh MB, Rothstein JL, Fusco A, Santoro M, Zitzelsberger H, Tallini G: RET/papillary thyroid cancer rearrangement in nonneoplastic thyrocytes: follicular cells of Hashimoto’s thyroiditis share low-level recombination events with a subset of papillary carcinoma. J Clin Endocrinol Metab 2006;91:2414–2423.
Wirtschafter A, Schmidt R, Rosen D, Kundu N, Santoro M, Fusco A, Multhaupt H, Atkins JP, Rosen MR, Keane WM, Rothstein JL: Expression of the RET/PTC fusion gene as a marker for papillary carcinoma in Hashimoto’s thyroiditis. Laryngoscope 1997;107:95–100.
Kim SK, Song KH, Lim SD, Lim YC, Yoo YB, Kim JS, Hwang TS: Clinical and pathological features and the BRAF(V600E) mutation in patients with papillary thyroid carcinoma with and without concurrent Hashimoto thyroiditis. Thyroid 2009;19:137–141.
Sadow PM, Heinrich MC, Corless CL, Fletcher JA, Nose V: Absence of BRAF, NRAS, KRAS, HRAS mutations, and RET/PTC gene rearrangements distinguishes dominant nodules in Hashimoto thyroiditis from papillary thyroid carcinomas. Endocr Pathol 2010;21:73–79.
Nikiforov YE: RET/PTC rearrangement – a link between Hashimoto’s thyroiditis and thyroid cancer...or not. J Clin Endocrinol Metab 2006;91:2040–2042.
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.