Nodular thyroid cancer. Diagnostic value of real time elastography.

BACKGROUND The most important aspect in the diagnostic approach of thyroid nodule is identifying the malignancy Elastography is a newly technique that measures the elasticity of tissue, after applying a external force, standardized control. US elastography is currently used in differentiation of malignant from benign lesions. PATIENTS This prospective study included 69 patients, mean age 50.08 +/- 12.43 years, 67 females and 2 men, with thyroid nodules on conventional US, with a volume higher than 0.20 ml. All patients underwent surgery after complete evaluation. Extemporaneous and postsurgical histopathological exam was performed in all cases. Tissue stiffness was scored from one (greatest elasticity) to 5 (no strain), according to the UENO scale. RESULTS In the 69 cases we diagnosed 107 nodules, which we analyzed. 27 nodules had score 1 on US elastography and 37 nodules had score 2. All nodules were benign on histopathological exam. Score 3 was found in 33 cases, 32 benign and one papillary carcinoma. Score 4 as found in 10 cases, all carcinomas. ES score of 4 is highly predictive for malignancy (sensitivity of 90.9%, specificity of 98.96%, positive predictive value of 100%, negative predictive value if 98.60%). The diagnostic quality of elastography was independent of the nodule volume. CONCLUSION US elastography has a good potential in diagnosing thyroid malignancy, independent of nodule volume, allowing the study of small nodules, less than 0.5 ml.