Introduction : The main role of fine needle aspiration cytology (FNAC) lies in the
differentiating between a malignant and benign thyroid nodule. It greatly influences the
treatment decision.
Aim : This study aimed to evaluate the accuracy of fine
needle aspiration cytology
(FNAC) in the diagnosis of thyroid nodules by evaluating the cytology–histopathology
correlation .
Materials and Methods : This is a prospective study of 49 diagnosed cases of thyroid
nodules who underwent FNAC and histological study of surgical biopsies for diagnosis at
Tishreen University Hospital , during the period between march 2017 – march 2018 .The
results were categorized according to Betheseda classification into:
insufficient for diagnosis, benign, follicular lesion of undetermined significance, follicular
neoplasm, suspicious for malignancy, and malignant sampling. The final histologic
diagnosis was considered the gold standard.
Results : The study included 49 cases presented with thyroid nodules who underwent
diagnostic thyroid FNAC. Female to male ratio was 7.2:1, and the mean age was 43.6
years.
Thirty –nine cases (79.6%) were diagnosed as benign, 3 cases (6.1%) as unsatisfactory , 2
cases (4.1%) as follicular neoplasm, 2 cases (4.1%) as suspicious for malignancy, 2 cases
(4.1%) as malignant, and 1 case (2%) as follicular lesion of undetermined significance.
Nodular goitre represented the majority of benign cases (62.8%), while papillary
carcinoma was the most frequent malignant lesion (83.3%).
Cytologic diagnoses were compared with their corresponding final histologic ones. FNAC
achieved a sensitivity of 83.3%, a specificity of 97.4%, a positive predictive value of
83.3%, a negative predictive value of 97.4%, a false positive rate of 2.5% , a false negative
rate of 16.6% , and a total accuracy of 95.5%.
Conclusion : FNA cytology is a sensitive, specific, and accurate initial diagnostic test for
the evaluation of patients with thyroid nodules.