High-frequency ultrasound (US) is increasingly used to help distinguish malignancy in patients with solitary or multiple nodules, and US-guided fine needle aspiration (FNA) has become the gold standard test for detecting thyroid cancer. Moreover, a further US-based risk stratification of thyroid nodules with Thyroid Imaging Reporting and Data System (TI-RADS) has been currently proposed for better and easier decision making. However, the presence of multiple nodules in the thyroid gland may decrease the diagnostic value of these preoperative diagnostic tools. The prevalence of incidental carcinoma identified on the final histological examination of the patients who underwent surgery for presumably benign thyroid diseases was previously reported to be roughly around 5 to 10%. Most of the previous studies also showed a lower risk of carcinoma in multinodular goitre (MNG) compared to solitary thyroid nodule (STN). However, some recent surgical series have reported that the risk of thyroid carcinoma in benign thyroid diseases is significantly higher than previously reported.
The purpose of the present study is to detect the accuracy of preoperative cytology and US-findings (TI-RADS) and the prevalence of thyroid carcinoma in patients operated for thyroid diseases and to discuss all malignancy risk factors in detail along with final histopathological report. Cytology-histology discrepant cases will also be further evaluated for sampling and interpretation errors, and possible solutions to increase the accuracy of preop testing are going to be proposed. The accuracy of the preference of total thyroidectomy procedure will be evaluated considering the prevalence of incidental carcinomas diagnosed postoperatively, and whether there are variations in the risk of malignancy with respect to final pathology of patients will also be discussed in detail.