Thyroid Fine-needle Aspiration: Histologic Correlation of the Diagnostic Categories of the Bethesda System with Emphasis on “Atypia of Undetermined Significance”: A 5-year Single-institution Experience
Yousef Alalawi, Laila M Moharram
Atypia of undetermined significance, Fine-needle aspiration, The Bethesda system for reporting thyroid cytopathology
Citation Information :
Alalawi Y, Moharram LM. Thyroid Fine-needle Aspiration: Histologic Correlation of the Diagnostic Categories of the Bethesda System with Emphasis on “Atypia of Undetermined Significance”: A 5-year Single-institution Experience. World J Endoc Surg 2019; 11 (3):76-79.
Aim: The aim of this study is to correlate the thyroid cytology diagnosis with the final histologic diagnosis, which is considered by us as the gold standard diagnostic test. Materials and methods: We studied all the thyroid cytopathology cases performed over the last 5 years at King Salman Military Hospital. We found a total of 1,048 thyroid fine-needle aspiration (FNA) cases, of which 318 cases had a follow-up histologic data. The cases are reported according to the Bethesda system for reporting thyroid cytopathology (BSRTC). The rate of malignancy is calculated for each diagnostic category (DC) as the proportion of malignant cases from the cases with histologic diagnosis. The false-positive cases are defined as the cases diagnosed in FNA as DC V or VI (suspicious for malignancy or malignant) and the following thyroid surgery showed a benign histology. The false-negative cases are those diagnosed in FNA as DC II (benign) and the following thyroid surgery showed a malignant diagnosis. Results: The percentage of false-positive cases for DC V (suspicious for malignancy) is 22.5%, while it is 2.38% for DC VI (malignant). The false-negative cases are those diagnosed in FNA as DC II (benign) and the following thyroid surgery showed a malignant diagnosis (8.7%). However, after reviewing the false-negative cases, eight cases were reclassified retrospectively, as “nondiagnostic”. The malignancy rate for our “atypia of undetermined significance (AUS)” cases is estimated to be between 21% and 35%.
Haugen BR, Alexander EK, Bible KC, et al. 2015 American thyroid association management guidelines for adult patients with thyroid nodules and differentiated thyroid cancer: the american thyroid association guidelines task force on thyroid nodules and differentiated thyroid cancer. Thyroid 2016;26(1):1–133. DOI: 10.1089/thy.2015.0020.
Rosen JE, Stone MD. Contemporary diagnostic approach to the thyroid nodule. J Surg Oncol 2006;94(8):649–661. DOI: 10.1002/jso.20701.
Ali SZ, Cibas ES. The Bethesda system for reporting thyroid cytopathology. Definitions, criteria and explanatory notes. New York: Springer; 2010.
Bongiovanni M, Spitale A, Faquin WC, et al. The Bethesda system for reporting thyroid cytopathology: a meta-analysis. Acta Cytol 2012;56(4):333–339. DOI: 10.1159/000339959.
Cibas ES, Ali SZ. The Bethesda system for reporting thyroid cytopathology. Am J Clin Pathol 2009;132:658–665. DOI: 10.1309/AJCPPHLWMI3JV4LA.
Espinosa De Ycaza AE, Lowe KM, Dean DS, et al. Risk of malignancy in thyroid nodules with non-diagnostic fine-needle aspiration: a retrospective cohort study. Thyroid 2016;26(11):1598–1604. DOI: 10.1089/thy.2016.0096.
Nikiforov YE, Seethala RR, Tallini G, et al. Nomenclature revision for encapsulated follicular variant of papillary thyroid carcinomaA paradigm shift to reduce overtreatment of indolent tumors. JAMA Oncol 2016;2(8):1023–1029. DOI: 10.1001/jamaoncol.2016.0386.
Ho AS, Sarti EE, Jain KS, et al. Malignancy rate in thyroid nodules classified as Bethesda category III (AUS/FLUS). Thyroid 2014;24(5):832–839. DOI: 10.1089/thy.2013.0317.
VanderLaan PA, Marqusee E, Krane JF. Clinical outcome for atypia of undetermined significance in thyroid fine-needle aspirations: should repeated FNA be the preferred initial approach? Am J Clin Pathol 2011;135(5):770–775. DOI: 10.1309/AJCP4P2GCCDNHFMY.
Alqahtani S, Alsobhi S, Alsalloum RI, et al. Surgical outcome of thyroid nodules with atypia of undetermined significance and follicular lesion of undetermined significance in fine needle aspiration biopsy. World J Endoc Surg 2017;9(3):100–103. DOI: 10.5005/jp-journals-10002- 1220.
Layfield LJ, Morton MJ, Cramer HM, et al. Implications of the proposed thyroid fine needle aspiration category of “follicular lesion of undetermined significance”: a five-year multi-institutional analysis. Diagn Cytopathol 2009;37(10):710–714. DOI: 10.1002/dc.21093.
Gocun PU, Karakus E, Bulutay P, et al. What is the malignancy risk for atypia of undetermined significance? three years’ experience at a university hospital in Turkey. Cancer Cytopathology 2014;122:604–610. DOI: 10.1002/cncy.21434.
Chandra S, Chandra H, Bisht SS. Malignancy rate in thyroid nodules categorized as atypia of undetermined significance or follicular lesion of undetermined significance: an institutional experience. J Cytol 2017;34(3):144–148. DOI: 10.4103/JOC.JOC_234_16.
Baloch ZW, Seethala RR, Faquin WC, et al. Noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP): a changing paradigm in thyroid surgical pathology and implications for thyroid cytopathology. Cancer Cytopathol 2016;124(9):616–620. DOI: 10.1002/cncy.21744.