DIAGNOSTIC ACCURACY OF THE FINE-NEEDLE ASPIRATION CYTOLOGY IN DIAGNOSIS OF SOLID SOLITARY THYROID NODULE
DOI:
https://doi.org/10.70520/kjms.v19i1.764Keywords:
Fine needle aspiration cytology, Thyroid nodule, Histopathology, Diagnostic accuracy, Sensitivity, SpecificityAbstract
Objective: To determine the diagnostic accuracy of fine needle aspiration cytology (FNAC) for solid solitary thyroid nodules, using histopathology as the reference standard.
Study Design: Cross-sectional validation study.
Place and Duration of Study: Department of ENT, Lady Reading Hospital (MTI), Peshawar, from 01 October 2024 to 31 March 2025.
Methodology: Adults (?18 years) with a solitary, predominantly solid thyroid nodule on ultrasonography underwent ultrasound-guided FNAC followed by surgical excision and histopathology. Cytology was reported using the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC). For diagnostic accuracy analysis, Bethesda II was considered benign (test negative) and Bethesda V–VI malignant (test positive); non-diagnostic (Bethesda I) and indeterminate categories (Bethesda III–IV) were excluded from the primary 2×2 analysis. Cytology and histopathology were interpreted independently with blinding to each other’s reports. Sensitivity, specificity, PPV, NPV, and accuracy were calculated with 95% confidence intervals (CI).
Results: A total of 110 patients were included; mean age was 45.81±16.24 years, and 63 (57.3%) were males. Histopathology confirmed 50 (45.5%) malignant and 60 (54.5%) benign nodules. FNAC showed sensitivity 84.00% (95% CI: 71.50–91.67), specificity 88.33% (95% CI: 77.79–94.22), PPV 85.71% (95% CI: 73.29–92.91), NPV 86.89% (95% CI: 76.17–93.23), and accuracy 86.36% (95% CI: 78.69–91.63).
Conclusion: In this single-centre surgical cohort, FNAC demonstrated good diagnostic performance for solid solitary thyroid nodules; however, false-negative and false-positive results occurred, so FNAC should be interpreted alongside clinical and ultrasound risk features, with repeat sampling or alternate techniques when suspicion persists.
References
1. Hegedüs L. Clinical practice. The thyroid nodule. N Engl J Med. 2004;351(17):1764–71. doi:10.1056/NEJMcp031436
2. Haugen BR, Alexander EK, Bible KC, Doherty GM, Mandel SJ, Nikiforov YE, et al. 2015 American Thyroid Association management guidelines. Thyroid. 2016;26(1):1–133. doi:10.1089/thy.2015.0020
3. Gharib H, Papini E, Paschke R, Duick DS, Valcavi R, Hegedüs L, et al. American Association of Clinical Endocrinologists guidelines. Endocr Pract. 2010;16(Suppl 1):1–43. doi:10.4158/EP.16.S1.1
4. Baloch ZW, Livolsi VA. Fine-needle aspiration of thyroid nodules: past, present, and future. Endocr Pract. 2004;10(3):234–41. doi:10.4158/EP.10.3.234
5. Cibas ES, Ali SZ. The Bethesda system for reporting thyroid cytopathology. Am J Clin Pathol. 2009;132(5):658–65. doi:10.1309/AJCPPHLWMI3JV4LA
6. Wang CC, Friedman L, Kennedy GC, Wang H, Kebebew E, Steward DL, et al. A large multicenter correlation study of thyroid nodule cytopathology and histopathology. Thyroid. 2011;21(3):243–51. doi:10.1089/thy.2010.0170
7. Ali SZ, Cibas ES. The Bethesda system for reporting thyroid cytopathology. 2nd ed. New York: Springer; 2018. doi:10.1007/978-3-319-25141-9
8. Awan MS, Ahmed S, Saeed M, Shahzad MF, Irfan M. Diagnostic accuracy of FNAC in thyroid nodules: a single-center study. Pak J Med Sci. 2020;36(3):360–4. doi:10.12669/pjms.36.3.1461
9. Khan MI, Rehman AU, Gul N, Arif A. Evaluation of fine needle aspiration cytology in the diagnosis of thyroid nodules. Khyber Med Univ J. 2018;10(4):204–8.
10. Shah S, Majeed R, Alamgir W, Rahim S, Khan S, Arif S, et al. Validity of FNAC in the diagnosis of solitary thyroid nodules. J Postgrad Med Inst. 2021;35(2):109–13.
11. Ogilvie JB, Piatigorsky EJ, Clark OH. Current status of fine needle aspiration for thyroid nodules. Adv Surg. 2006;40:223–38. doi:10.1016/j.yasu.2006.03.004
12. Bukhari MH, Niazi S, Hanif G, Qureshi SS, Bashir N, Akhtar MS, et al. An updated audit of fine needle aspiration cytology procedure of solitary thyroid nodule. Diagn Cytopathol. 2008;36(2):104–12. doi:10.1002/dc.20751
13. 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. doi:10.1159/000339959
14. Renshaw AA, Pinnar N, Jiroutek M, Cibas ES. Fine needle aspiration of follicular lesions of the thyroid. Am J Clin Pathol. 2001;116(4):483–8. doi:10.1309/XJLP-4TGX-25L6-MY1X
15. Wang CC, Friedman L, Kennedy GC, Wang H, Kebebew E, Steward DL, et al. A large multicenter correlation study of thyroid nodule cytopathology and histopathology. Thyroid. 2011;21(3):243–51. doi:10.1089/thy.2010.0170
16. Bakhos R, Selvaggi S, De Jong S, Gordon D, Pitman MB, Faquin WC. Fine-needle aspiration of the thyroid: rate and causes of cytohistopathologic discordance. Diagn Cytopathol. 2000;23(4):233–7. doi:10.1002/1097-0339(200010)23:4<233::AID-DC10>3.0.CO;2-A
17. Lan L, Luo Y, Zhou M, Huo L, Chen H, Zuo Q, Deng W. Comparison of diagnostic accuracy of thyroid cancer with ultrasound-guided fine-needle aspiration and core-needle biopsy: a systematic review and meta-analysis. Front Endocrinol (Lausanne). 2020;11:44. doi:10.3389/fendo.2020.00044
18. Abdel Latif M, El Rakhawy MM, Saleh MF. Diagnostic accuracy of ultrasound elastography and DWI MRI vs FNAC in thyroid nodules. Egypt J Radiol Nucl Med. 2021;52:256. doi:10.1186/s43055-021-00640-9
19. Abdolali F, Shahroudnejad A, Hareendranathan AR, Jaremko JL, Noga M, Punithakumar K. Role of AI in sonographic diagnosis of thyroid cancer: a systematic review. Front Endocrinol (Lausanne). 2020;11:44. doi:10.3389/fendo.2020.00044
20. Osseis M, Jammal G, Kazan D, Noun R. Comparison between fine needle aspiration cytology with histopathology in the diagnosis of thyroid nodules. J Pers Med. 2023;13(8):1197. doi:10.3390/jpm13081197.
