A Clinical Study Of Diagnostic Performance Of Ultrasound-Guided Core Needle Biopsy In Thyroid Nodules

Objective:1. To explore the diagnostic value of ultrasound-guided core needle biopsy (CNB) in the differential diagnosis of thyroid nodules.2. To assess the accuracy of ultrasound-guided CNB for evaluating the calcified thyroid nodules.Materials and Methods:1. Between January 2008 and February 2014,4,784 thyroid nodules underwent ultrasound-guided CNB in our institution and were retrospectively reviewed. Biopsy findings were compared to the surgical specimen for the 1952 patients who subsequently underwent hemi-or total thyroidectomy for determining accuracy sensitivity, specificity, positive predictive values and negative predictive values of CNB.2. Between January 2009 and December 2014, US-guided CNB was performed in our institution for 2328 calcified thyroid nodules. All of thyroid CNB results were divided into six diagnostic categories according to the Bethcsda System for Reporting Thyroid Cytopathology (BSRTC).Results:1. The constituent ratio of Each Subtype for the CNB results is1) Nondiagnostic/unsatisfactory:1.7%2) Benign:30.4%3) Atypia of undetermined significance/follicular lesion of undetermined significance:2.0%4) Follicular neoplasm/suspicious for a follicular neoplasm:4.3%5) Suspicious for malignancy:10.4%6) Malignant:51.1%2. Postoperative Malignancy Rates of Each subtype for the finding of CNB is 45.5%、8.5%,16.7%、25.0%、93.9%、99.7% respectively.3. The diagnostic accuracy, sensitivity, specificity, positive predictive value and negative predictive value of CNB for the detection of malignancy in thyroid nodules were 91.2%(1914/2099); 97.6%(1730/1772); 95.0%(304/320); 98.7% (1730/1753); 87.9%(304/346) respectively.4. Non-diagnostic rate of thyroid nodules with microcalcification, within macr-ocalcification and peripheral macrocalcification is 1.5%; 1.7%; 3.7% respectively.The inconclusive rate of thyroid nodules with microcalcification,within macrocalcification and peripheral macrocalcification is 6.8%;11.4%;13.0% respectively.5. The inconclusive rate of calcified thyroid nodules with 18G and 20G is 8.3%、 11.4% respectively.Conclusion:1. Non-diagnostic rate of CNB in our study was lower than that of previous FNA results.2. Positive predictive value of CNB with grade Ⅴ and Ⅵ in our study was higher than that of previous FNA results.3. CNB can minimise the non-diagnostic results of repeat FNA for thyroid nodules with previous, non-diagnostic FNA results.4. Even the CNB result is benign, thyroid nodules with diffuse diseases repeat biopsy is necessary, in order to avoid false negative results.5. Thyroid nodules with macrocalcification also showed a significantly higher nondiagnostic rate than those with microcalcification.6. The Conclusive of diagnostic rate for Thyroid nodules with calcification with 18G is batter then that of 20G...