The diagnostic accuracy of ultrasound-guided fine-needle aspiration biopsy for thyroid nodules three centimeters or larger in size

Background and Purpose Whether under ultrasonography (US) guidance or not, fine‐needle aspiration biopsy (FNAB) has some limitations, particularly in larger nodules. In this study, we aimed to evaluate the diagnostic value of US‐guided fine‐needle aspiration biopsy (US‐FNAB) in thyroid nodules equal to or larger than 3 cm. Materials and Methods Data of 267 patients operated for nodular goiter in the period of January 2006 and March 2012 were reviewed retrospectively. The study group (40 males, 104 females; mean age 42.3 ± 12.3, between 17 and 71) consisted of patients with nodules with a diameter of 3 cm or larger. Patients with nodules less than 3 cm in diameter were considered as the control group (27 males, 96 females; mean age 44.4 ± 11.9, between 18 and 71). Results For nodules smaller than 3 cm, US‐FNAB had an accuracy rate of 60% and a false negativity rate of 21.9%. In nodules equal to or larger than 3 cm, the accuracy rate of US‐FNAB was 80%, with a false negativity rate of 6.7%. Malignancy was observed in 16% of the study group and 42.3% of the control group. Conclusion This study showed that increased nodule diameter is not associated with limitations in the diagnostic value of US‐FNAB. We also found that the malignancy rate was smaller for larger nodules. This finding reflects the importance of accurate and rational diagnostic work‐up and clinical management for detecting malignancy and surgical decision‐making. Diagn. Cytopathol. 2015;43:622–628. © 2015 Wiley Periodicals, Inc.