INTRODUCTION: This study aims to compare the preoperative sonographic findings, fine-needle aspiration biopsy (FNAB) and postoperative histopathological results in patients who underwent total thyroidectomy.
METHODS: A total of 884 patients (199 males, 685 females; mean age 46.8±12.7 years; range, 16 to 82 years) who underwent total thyroidectomy were included. Thyroid ultrasonography was performed in all patients with an initial diagnosis of thyroid nodules. Sonographic findings of thyroid nodules were evaluated. The sonographic characteristics were the number of nodules and sizes, having microcalcifications, having irregular margins and echogenicity. Sonographic malignancy scores were calculated due to sonographic findings. All thyroidectomy specimens were sent for pathological evaluation. The specimens were divided into two groups as benign and malignant groups, due to pathological evaluation. Groups were compared in terms of preoperative sonographic findings, FNAB and postoperative histopathological results.
RESULTS: The sonographic malignancy scores were statistically higher in malignant group than in benign group (p=0.001). Nodule size was smaller in malignant group than in benign group (p=0.001). Capsule irregularity rate was statistically higher in malignant group than in benign group (p=0.001). Hypoechogenicity rate was statistically higher in malignant group than in benign group (p=0.001). There was a statistically significant consistency between pathology and FNAB results (kappa=0.478, p=0.001). The sensitivity, specificity, positive predictive and negative predictive values of FNAB were 55.7%, 92.4%, 72.5% and 82.9%, respectively.
DISCUSSION AND CONCLUSION: Although the thyroid FNAB has acceptable sensitivity and specificity, it is not effective alone in establishing a decision of operation. Risk factors of thyroid malignancy should also be considered when assessing FNAB results.