Diagnostic accuracy of fine needle aspiration cytology for thyroid nodules under the 2023 Bethesda system: a retrospective analysis with future perspectives on artificial intelligence and molecular integration
DOI:
https://doi.org/10.18203/issn.2454-5929.ijohns20262379Keywords:
Thyroid swelling, Fine needle aspiration cytology, Histopathology, Bethesda system 2023, Artificial intelligence, Molecular diagnostics, Colloid nodular goitreAbstract
Background: Thyroid swellings are common clinical presentations in ENT and pose diagnostic challenges in differentiating benign from malignant lesions through clinical and ultrasonographic evaluation alone. FNAC offers a minimally invasive, rapid, cost-effective preoperative tool, though it is limited by an inability to differentiate certain indeterminate categories, such as follicular adenoma from follicular carcinoma. Modern adjuncts, including artificial intelligence (AI) and molecular testing, are increasingly explored to bridge these diagnostic gaps.
Methods: This retrospective study was conducted in the Department of ENT, Father Muller Medical College, Mangalore, Karnataka, India between 1st October 2023 and 31st October 2025, involving 40 patients who presented with thyroid swellings and underwent preoperative FNAC followed by total thyroidectomy. Cytological results were classified utilizing the updated 2023 (3rd Edition) Bethesda system for reporting thyroid cytopathology. The FNAC findings were correlated with postoperative histopathological reports to determine sensitivity, specificity, predictive values, and accuracy.
Results: Out of 40 thyroid swellings, Colloid nodular goitre was the most frequent condition on fine needle aspiration cytology (FNAC) (72.5%). Under the updated 2023 Bethesda system, 80% of cases were categorized as benign (Category II), with 5% demonstrating atypia of undetermined significance (AUS) (category III). Histopathology confirmed colloid nodular goitre in 60% and malignancy in 5% of cases. FNAC-histopathology correlation showed high concordance, demonstrating excellent diagnostic accuracy for benign and malignant lesions, with a sensitivity of 100%, specificity of 88.89%, positive predictive value of 96.88%, negative predictive value of 100%, and an overall diagnostic accuracy of 97.5%.
Conclusions: FNAC is an essential first-line diagnostic tool for the preoperative evaluation of thyroid swellings, guiding surgical planning with high sensitivity and specificity. However, isolated false-positive interpretations highlight the inherent limitations of standard cytomorphology, underscoring the future necessity of integrating emerging molecular classifiers and AI-driven digital pathology to optimize the management of indeterminate nodules.
References
Alqahtani SM. Post-thyroidectomy hypoparathyroidism: A clinical surgical dilemma. Saudi Med J. 2024;45(12):1305-11.
Allen M, Palma C, Branco C, Resende C, Vieira N, Silva AL, et al. Thyroid surgery outcomes in a 4-year series with intraoperative neuromonitoring: a retrospective cohort study. Gland Surg. 2025;14(7):1230-41.
Scheller B, Culié D, Poissonnet G, Dassonville O, D'Andréa G, Bozec A. Recent Advances in the Surgical Management of Thyroid Cancer. Curr Oncol. 2023;30(5):4787-804.
Tessler FN, Middleton WD, Grant EG, Hoang JK, Berland LL, Teefey SA, et al. ACR Thyroid Imaging, Reporting and Data System (TI-RADS): White Paper of the ACR TI-RADS Committee. J Am Coll Radiol. 2017;14(5):587-95.
Gharib H, Papini E, Paschke R, Duick DS, Valcavi R, Hegedüs L, et al. American Association of Clinical Endocrinologists, Associazione Medici Endocrinologi, and European Thyroid Association Medical guidelines for clinical practice for the diagnosis and management of thyroid nodules: executive summary of recommendations. Endocr Pract. 2010;16(3):468-75.
Gharib H, Papini E, Garber JR, Duick DS, Harrell RM, Hegedüs L, et al. American association of clinical endocrinologists, American college of endocrinology, and associazione medici endocrinologi medical guidelines for clinical practice for the diagnosis and management of thyroid nodules--2016 update. Endocr Pract. 2016;22(5):622-39.
Pusztaszeri M, Krane JF, Faquin WC. Follicular neoplasm of the thyroid: cytomorphologic findings on fine-needle aspiration and its role in surgical triage. Cancer Cytopathol. 2014;122(5):363-70.
Horne MJ, Chhieng DC. The clinical utility of fine-needle aspiration in the diagnosis and management of thyroid neoplasms. Curr Opin Oncol. 2011;23(1):11-7.
Azaryan I, Maxwell C, Tran DH, Sipos JA, Endo M. Molecular testing for the management of indeterminate thyroid nodules. Endocr Relat Cancer. 2026;33(2):e250258.
Chowdhury R, Hier J, Payne KE, Abdulhaleem M, Dimitstein O, Eisenbach N, et al. Impact of Molecular Testing on Surgical Decision-Making in Indeterminate Thyroid Nodules: A Systematic Review and Meta-Analysis of Recent Advancements. Cancers (Basel). 2025;17(7):1156.
Negrelli M, Frascarelli C, Maffini F, Mangione E, Di Tonno C, Lombardi M, et al. Fusco N. Artificial Intelligence in Thyroid Cytopathology: Diagnostic and Technical Insights. Cancers (Basel). 2025;17(21):3525.
Dey P, Savala R, Saikia UN. Application of Artificial Intelligence-Based Transfer Learning Models to the Bethesda System for Thyroid Cytopathology. Cytopathology. 2026;37(3):247-54.
Unnikrishnan AG, Menon UV. Thyroid disorders in India: An epidemiological perspective. Indian J Endocrinol Metab. 2011;15(2):S78-81.
Mathur P, Sathishkumar K, Chaturvedi M, Das P, Sudarshan KL, Santhappan S, et al. Cancer Statistics, 2020: Report From National Cancer Registry Programme, India. JCO Glob Oncol. 2020;6:1063-75.
Bouvet M, Feldman JI, Gill GN, Dillmann WH, Nahum AM, Russack V, et al. Surgical management of the thyroid nodule: patient selection based on the results of fine-needle aspiration cytology. Laryngoscope. 1992;102(12 Pt 1):1353-6.
Mandreker SR, Nadkarni NS, Pinto RG, Menezes S. Role of FNAC as the initial modality in the investigation of thyroid lesions. Acta Cytol. 1995;39:898-904.
Agrawal S. Diagnostic accuracy and role of fine needle aspiration cytology in management of thyroid nodules. J Surg Oncol. 1995;58(3):168-72.
Bongiovanni M, Spitale A, Faquin WC, Mazzucchelli L, Baloch ZW. The Bethesda System for Reporting Thyroid Cytopathology: a meta-analysis. Acta Cytol. 2012;56(4):333-9.
Ali SZ, Baloch ZW, Cochand-Priollet B, Schmitt FC, Vielh P, VanderLaan PA. The 2023 Bethesda System for Reporting Thyroid Cytopathology. Thyroid. 2023;33(9):1039-44.
Deveci MS, Deveci G, LiVolsi VA, Baloch ZW. Fine-needle aspiration of follicular lesions of the thyroid. Diagnosis and follow-Up. Cytojournal. 2006;3:9.
Gardner HA, Ducatman BS, Wang HH. Predictive value of fine-needle aspiration of the thyroid in the classification of follicular lesions. Cancer. 1993;71(8):2598-603.
Handa, Uma; Garg, Sukant; Mohan, Harsh; Nagarkar, Nitin1. Role of fine needle aspiration cytology in diagnosis and -management of thyroid lesions: A study on 434 patients. J Cytol. 2008;25(1):13-7.
Kessler A, Gavriel H, Zahav S, Vaiman M, Shlamkovitch N, Segal S, et al. Accuracy and consistency of fine-needle aspiration biopsy in the diagnosis and management of solitary thyroid nodules. Isr Med Assoc J. 2005;7(6):371-3.
Gupta M, Gupta S, Gupta VB. Correlation of fine needle aspiration cytology with histopathology in the diagnosis of solitary thyroid nodule. J Thyroid Res. 2010;2010:379051.
Sengupta A, Pal R, Kar S, Zaman FA, Sengupta S, Pal S. Fine needle aspiration cytology as the primary diagnostic tool in thyroid enlargement. J Nat Sci Biol Med. 2011;2(1):113-8.
Esmaili HA and Taghipour H. Fine-Needle Aspiration in the Diagnosis of Thyroid Diseases: An Appraisal in Our Institution. ISRN Pathol. 2012;912728:4.
Kumar A, Bhadouriya SKS, Narain P, Chauhan JPS, Bharti B, Singh J. Comparative study of FNAC and histopathology of thyroid swellings, diagnostic accuracy and role in its management. Int J Otorhinolaryngol Head Neck Surg. 2017;3:885-92.
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