Background: Fine needle aspiration cytology (FNAC) is considered the gold standard diagnostic test for the
diagnosis of thyroid nodules. FNAC is a cost effective procedure that provides specific diagnosis rapidly with
minimal complications. Based on the cytology findings, patients could be followed in cases of benign diagnosis and
subjected to surgery in cases of malignant diagnosis therefore decreasing the rate of unnecessary surgery.
Aim of work: To correlate pre-operative fine needle aspiration cytology (FNAC) to post-operative paraffin section
results in diagnosis of solitary thyroid nodule (STN).
Patients and methods: This is a prospective study, it was performed on 30 patients diagnosed as solitary thyroid
nodule; the results for FNAC and histopathological examination were reviewed, evaluated and correlated.
Results: On FNAC, out of 30 cases there were 19 benign lesions; 17 (56.66%) cases were true negative (TN) and
2 (6.67%) cases were false negative (FN).
There were 11 (36.67%) of undetermined significance or suspicious neoplastic lesions diagnosed by FNAC; 10
(33.33%) cases were true positive (TP) and only one (3.33%) case was false positive (FP). After comparison of
results of FNAC with histopathology, the sensitivity, specificity, accuracy, positive predictive value and negative
predictive value were 83.33%, 94.44%, 90%, 90.91% and 89.47%, respectively.
Conclusion: Fine needle aspiration was a significantly better predictor of malignancy, we recommend this
procedure in the light of other investigations as a primary investigation of thyroid lesions in a patient with solitary
thyroid nodules as it should be advised for exclusion of malignancy.