Context: There is a high prevalence of thyroid nodules on ultrasonographic US exam. However, most of them are benign. US criteria may help to decide cost-effective management. Objective: To develop a standardized US characterization and reporting data system of thyroid lesions for clinical management: the TIRADS system. Design: A prospective study using the TIRADS system, which is based on the concepts of the Breast Imaging Reporting and Data System, developed by the American College of Radiology. Materials: A correlation of the US findings and FNAB results in 1956 lesions biopsied under US guidance, and studied histologically during an 8 year-period, divided in 3 stages. In the first stage ten US patterns were defined. In the second stage, 4 TIRADS groups were defined according to risk. The % of malignancy were followed: TIRADS 2 (0% malignancy), TIRADS 3 (less than 5% malignancy), TIRADS 4 (5-80% malignancy) and TIRADS 5 (over 80% malignancy). Results: The TIRADS classification was evaluated at the third stage of the study in a sample of 1097 nodules (benign: 703; follicular lesions: 238 and carcinoma: 156). Sensitivity, Specificity, PPV, NPV and accuracy were: 88%, 49%, 49%, 88% and 94% respectively. The ratio of benign/malignant or follicular FNAB results currently is 1.8. Conclusions: The TIRADS system has allowed us to improve patient management and cost-effectiveness avoiding unnecessary FNAB. Also, we have established standard codes to be used both for radiologists and endocrinologists.
Horvath, E,
TI-RADS: An US Classification of Thyroid Nodules Related to Cancer Risk. Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL.
http://archive.rsna.org/2010/9016467.html
