Evaluation of results of fine needle aspiration and pathology of thyroid nodules in thyroidectomy Patients

Introduction: The most common manifestation of thyroid malignancy is thyroid nodule. In few studies, pathologic findings of malignancy were seen in patients who were undergone thyroidectomy because of causes other than malignancy. The aim of this study was the evaluation of the rate of malignancy in patients who undergone thyroidectomy. Methods: In this retrospective multi central study, 765 out of 802 patients who had undergone thyroidectomy in Bandar Abbas and Tehran Taleghani hospitals were evaluated from 1376 till 1386. The FNA (Fine Needle Aspiration) results before operation and pathologic results after operation were classified by AACE standard into benign (multi nodular goiter,hoshimotoo's thyroiditis,simple or blood containing cysts, and follicular adenomas) and malignant groups (papillary malignancy of thyroid, primary lymphoma of thyroid, follicular malignancy of thyroid, hurtle cell malignancy of thyroid ,malignant metastatic lesions). The data were analyzed with SPSS software. Results: Preoperative cytology showed that 432 cases (73.8%) were benign, 79 of cases (13.8%) were malignant, 55 (9.6%) suspicious, 5 (0.9%) inadequate and 11 (1.9%) were unremarkable. Pathologic results of 222 patients (29%) were malignant and 534 (71%) were benign. Specificity, sensitivity, positive and negative predictive value of FNA were 56.5, 97.6, 88.6 and 87.2, respectively. Conclusion: In this study, FNA had low sensitivity for diagnosis of malignancy of thyroid. Results showed that despite a negative FNA result, multiple FNAs and follow up of thyroid are recommended.