Accuracy of Fine Needle Aspiration in Diagnosing Thyroid Cancer in a Tertiary Care Centre

Introduction: Cancer is one of the leading causes of morbidity and mortality worldwide. Thyroid cancer is the fourth most common cancer and the second most common in female specifically. FNA is the most reliable method for investigating thyroid nodules with sensitivity between 89% to 98%, and specificity of 92%. Our aim is to determine the accuracy of FNA in diagnosing thyroid nodules in KAUH and identifying factors that might affect its accuracy. Methods: A retrospective review of all patients who underwent thyroidectomy at King Abdulaziz University Hospital between 2010-2014 was performed. Chi-square test was used to test the associations between FNA result and histopathological diagnosis. One way-ANOVA tests were used to compare the means of size of the nodules, age and BMI of the patients for the different FNA diagnoses. Results: A Total of 265 thyroidectomies were reviewed. Fifty-one of the thyroid nodules were benign. Papillary was the most common type of thyroid cancer accounting for 82.1%. Using Bethesda System for Reporting Thyroid Cytopathology Classification; 8.2% were unsatisfactory for diagnosis, 23.1% were benign, 35.8 % showed follicular lesions, were 5.2% were suspicious for malignancy and 23.9% were malignant. A comparison between FNA and the histopathology reports revealed an FNA sensitivity of 87.5% and specificity of 38.9% with positive predictive value of 57.6% and a negative predictive value of 76.6% in KAUH. Size of nodule, age and BMI of the patient did not affect FNA accuracy (p-value >.05). Conclusion: This study confirms that FNA is a highly reliable tool to assess thyroid nodule whether it is benign or malignant. Size of the nodule, age and BMI of the patient did not affect the accuracy of FNA. the accuracy of FNA and the factors that might affect its sensitivity and specificity. The aim of this paper is to identify the accuracy of FNA in diagnosing thyroid nodules, and compares it to the corresponding final histopathologic results and possibly identifying the factors that might affect its accuracy.