Contrast-enhanced ultrasonography features of papillary thyroid carcinoma for predicting cervical lymph node metastasis

Ying Liu; Hong Zhou; Peng Yang; Yang Zhou; Jian Wu; Changyu Chen; Ming Ye; Jing Luo

doi:10.3892/etm.2017.5087

Contrast-enhanced ultrasonography features of papillary thyroid carcinoma for predicting cervical lymph node metastasis

Exp Ther Med. 2017 Nov;14(5):4321-4327. doi: 10.3892/etm.2017.5087. Epub 2017 Sep 1.

Authors

Ying Liu¹, Hong Zhou¹, Peng Yang², Yang Zhou¹, Jian Wu³, Changyu Chen¹, Ming Ye¹, Jing Luo³

Affiliations

¹ Department of Ultrasound, The Third People's Hospital of Chengdu and The Affiliated Clinical Medical College of Southwest Jiao Tong University, Qingyang, Chengdu, Sichuan 610031, P.R. China.
² Department of Pathology, The Third People's Hospital of Chengdu and The Affiliated Clinical Medical College of Southwest Jiao Tong University, Qingyang, Chengdu, Sichuan 610031, P.R. China.
³ Department of Thyroid Surgery, The Third People's Hospital of Chengdu and The Affiliated Clinical Medical College of Southwest Jiao Tong University, Qingyang, Chengdu, Sichuan 610031, P.R. China.

Abstract

The present study was performed to evaluate the predictive value of contrast-enhanced ultrasonography (CEUS) for the risk of cervical lymph node metastasis (LNM) in papillary thyroid carcinoma (PTC). Between May 2014 and November 2016, 42 patients who received surgery for suspicious PTCs were enrolled in the present study. Each individual underwent CEUS with conventional ultrasound (US), preoperative US-guided fine needle aspiration and personalized surgery. Subsequently, the microvascular density (MVD) of all surgical specimens was measured. According to the results of surgical histopathology, individuals were divided into two groups: LNM⁺ (PTCs with LNM), and LNM^- (PTCs without LNM). Clinicopathological characteristics, CEUS enhancement patterns, perfusion parameters and measurements of MVD were compared. The correlation between quantitative variables and LNM was analyzed using Spearman's correlation analysis. Compared with that in the LNM^- group, patients in the LNM⁺ group were younger (P<0.05) and had a larger mean tumor size (P<0.05). The incidence ratio of patients who were ≤45 years old (P<0.05), tumors >10 mm in size (P<0.05) and capsular infiltration (P<0.05) were statistically higher in the LNM⁺ group. Following the use of a novel classification system, the ratio of PTCs with early partial hyper-enhancement was identified to be significantly higher in the LNM⁺ group (P<0.01). The mean intensity, intensity increase velocity, MVD ratio and mean intensity ratio of intratumoral/peripheral thyroid parenchyma (MIR) were statistically higher in the LNM⁺ group compared with that in the LNM^- group (all P<0.05). MIR was identified to be positive correlated with LNM (P<0.05). A MIR value of 0.86 was the optimal threshold of LNM in PTCs. In conclusion, LNM may rely on the local rich blood supply of PTC lesions. Partial hyper-enhancements of CEUS and higher values of MIR may suggest a high risk for LNM in PTC.

Keywords: contrast-enhanced ultrasonography; fine needle aspiration; lymph node metastasis; mean intensity ratio of intratumoral/peripheral thyroid parenchyma; microvascular density; papillary thyroid carcinoma.