Introduction: Real-time elastography (RTE) is a noninvasive ultrasound method of estimation of tissue stiffness by measuring the degree of local tissue displacements after a small compression. Recent data has shown indicate on its ability to differentiate benign and malignant tumors. The aim of the study was to evaluate the diagnostic accuracy of RTE in the diagnosis of malignant and benign thyroid nodules.
Material and methods: A total of 75 thyroid nodules in 54 patients: 44 females and 10 males aged 2877 years were examined using conventional ultrasonography (US), fine-flow CD imaging and RTE. Thyroid US and RTE were performed by 3 examiners using a real-time Hitachi Hivision Preirus machine with linear transducer of 512 MHz. All nodules underwent fine-needle aspiration biopsy (FNAB) and patients with malignant and suspicious cytological results were referred to surgery. The final diagnosis was based on FNAB results in patients with benign cytology and on the histopathology reading in those who underwent surgery. The elasticity score (ES) from 1 to 5 was determined for each nodule according to Ueno classification.
Results: Elasticity score (ES) 4 or 5 was found in 19/22 (86.5%) thyroid cancers and in only 1/34 (3%) benign nodule. This was strongly indicative for malignancy (P<0.0001) with sensitivity 86%, specificity 97%, positive predictive value (PPV) 95% and negative predictive value (NPV) 91%. Among 9 suspicious nodules 3 appeared to be malignant (1 oxyphillic cell type carcinoma, 2 papillary carcinomas) and 6 were benign. All malignant nodules had ES 4 and benign ones had ES 2 or 3.
Conclusions: RTE is a highly sensitive and specific method of diagnosing thyroid nodules. This technique can be employed in selecting thyroid nodules for the fine-needle aspiration biopsy.
30 Apr - 04 May 2011
European Society of Endocrinology