Application value of The Thyroid Imaging Reporting and Data System and The Bethesda System for Reporting Thyroid Cytopathology in thyroid nodules

Abstract

Objective To investigate the value of Thyroid Imaging Reporting and Data System (TI-RADS) and The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) for thyroid nodules. Methods A total of 216 thyroid nodules were obtained from 207 patients with thyroid nodules under ultrasound-guided fine needle aspiration biopsy (US-FNAB) from November 2013 to April 2015 at the General Hospital of Tianjin Medical University. 170 nodules were confirmed by surgical pathology of Tianjin Medical University General Hospital and Tianjin Medical University Cancer Hospital, and 46 nodules were followed up for more than 6 months. The classifications of TI-RADS and TBSRTC were performed for all thyroid nodules. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of ultrasound TI-RADS and cytology TBSRTC in differential diagnosis of benign and malignant thyroid nodules were calculated using surgical pathological results and ultrasound follow-up results as the ″gold″ standard. Results 170 thyroid nodules were confirmed by operational pathology, including 146 malignant nodules, all of which were papillary thyroid carcinoma; and 24 benign nodules, which were 16 nodular goiters, 6 Hashimoto′s thyroiditis, and 2 follicular adenomas. The thyroid nodules were cytologically evaluated as TBSRTC class Ⅱ, and ultrasonically evaluated as TI-RADS class 3, and no significant changes in the size and morphology of the nodules at 6 to 15 months , which were considered benign. Among the 216 thyroid nodules, 8 were TI-RADS class 3, 19 were TI-RADS class 4a, 55 were TI-RADS class 4b, 130 were TI-RADS class 4c, 4 were TI-RADS class 5. Among them, there were 0, 5, 23, 114, and 4 malignant thyroid nodules, respectively. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of TI-RADS for differential diagnosis of benign and malignant thyroid nodules were 100%, 11.4%, 71.3%, 70.2%, and 100%, respectively. Of the 216 thyroid nodules, 57 were TBSRTC classⅡ, 24 were TBSRTC class Ⅲ, 3 were TBSRTC class Ⅳ, 83 were TBSRTC class Ⅴ, and 49 were TBSRTC class Ⅵ. Among them, there were 2, 16, 2, 77, 49 thyroid malignant nodules, respectively. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of TBSRTC for differential diagnosis of benign and malignant thyroid nodules were 98.4%, 90.2%, 95.8%, 95.5%, and 96.5%, respectively. In the subgroup of nodules with malignant classification on cytology TBSRTC, their ultrasound classifications were all TI-RADS 4a-5. Conclusions TI-RADS contribute to select the target nodule to puncture. TBSRTC has a high diagnostic capability, and provides an important basis for clinical treatment of nodules. The combination of the two methods will further improve the diagnosis of malignant nodules. Key words: Ultrasonography; Fine needle aspiration biopsy; Cytopathology; Thyroid nodules