RESUMO
Fine needle aspiration [FNA] cytology was performed to diagnose and evaluate the accuracy of solitary thyroid nodule [STN]. Histopathology was used as gold standard to compare the results of FNA. The study included 180 patients [138 females and 42 males], from different Ministry Hospitals in Riyadh, Kingdom of Saudi Arabia [KSA] between January 2008 - June 2010. All cases were investigated and examined clinically and the final diagnosis was STN. The cases were operated and evaluated for histopathological findings. On FNA 138 patients [76.6%] had benign lesion, 25 patients [14%] showed unsatisfactory lesions and 17 patients [9.4%] had malignant lesions. On histopathology, 144 patients [80%] were confirmed to have benign lesions and 36 patients [20%] have malignant lesions. The commonest type of malignancy in FNA and histopathology was papillary carcinoma. The results of FNA compared to the histopathological results showed 80% sensitivity, 20% specificity, 10% positive predictive value, 90% negative predictive value and 26% diagnostic accuracy. FNA is a more sensitive technique than specific in detecting thyroid malignancy