Diagnostic Accuracy of Fine Needle Aspiration for Solitary and Multiple Thyroid Nodules in a Tertiary Care Center

Thyroid nodules are common in clinical practice. They are usually benign, but malignancy must be ruled out. Fine needle aspiration (FNA) biopsy of the thyroid is a rapid and cost-effective procedure in the initial evaluation of a thyroid nodule, but its results may be inaccurate in 10% to 30% of cases. This prospective observational study was conducted to determine the prevalence of thyroid cancer, its related findings, and the diagnostic accuracy of preoperative FNA in a tertiary care center.
We prospectively studied the medical records of 345 subjects, who underwent thyroid resection in the university hospital setting over a 4-year period. Age, gender, FNA and pathologic reports, and whether the lesion was multinodular or a solitary nodule were determined.
The sensitivity and specificity of FNA were 64.96% and 62.76%, respectively. The positive predictive value of the test for the diagnosis of malignant nodules was 59.30% and its negative predictive value was 68.20%. In 63.5% of the patients, the preoperative FNA matched the surgical histopathology results. The presence of multinodular goiter was an important risk factor for thyroid malignancy. Fifty-two subjects had papillary microcarcinoma and the rate of aggressive behavior was considerable in this group.
Although fine needle aspiration biopsy is the most important step in the workup of the thyroid nodules, it may miss a significant number of malignant lesions. Therefore, there is a mandatory need to evolve other clinical and laboratory adjuncts, which assists the clinicians with the interpretation of FNA more accurately.