MRI and ultrasonography detection of cervical lymph node metastases in differentiated thyroid carcinoma before reoperation.
OBJECTIVE
The purpose of this study was to compare the diagnostic capabilities of magnetic resonance imaging (MRI) and ultrasonography (US) for cervical lymph nodal metastases in differentiated thyroid carcinoma (DTC) before reoperation.


METHODS
From June 2011 to May 2013, preoperative MRI and ultrasound data were collected from differentiated thyroid cancer patients who underwent a reoperation. The following characteristics were assessed: the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of MRI and US. The MRI and ultrasound findings were correlated with the histological diagnosis after reoperation.


RESULTS
One hundred and thirty-eight cases were included in the analysis. 88.4% (122/138) of which had evidence of residual thyroid cancer tissue or metastatic nodal involvement at final histology. Lymph nodal metastases were confirmed in the central compartment in 76.42% (81/106) of patients and in lateral compartment in 73.28% (85/116) of patients. The sensitivity, specificity and accuracy of MRI VS US for detecting central compartment metastases was 75% VS 41.67% (P=0.04), 90.91% VS 100% (P=1) and 80% VS 60% (P=0.618), respectively; For detecting lateral compartment metastases was 83.33% VS 77.78% (P=1), 25% VS 50% (P=0.606) and 65.38% VS 69.23% (P=1), respectively. There was statistically significant difference between the sensitivity of MRI and ultrasound for diagnose of central compartment metastases. The MRI features with the greatest correlation with positive lymph nodal metastases were fusion and enhancing lesions. The ultrasound features with the greatest correlation with positive lymph nodal metastases were hypoechoic and microcalcifications.


CONCLUSIONS
MRI is more sensitive than ultrasonography in detecting central compartment metastases in papillary thyroid carcinoma. There is no significant difference in diagnosis of lateral neck node metastases between MRI and US.
Department of General Surgery, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan, China.
Zeming
Z
Liu
Department of General Surgery, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan, China.
Xueqiong
X
Xun
Department of General Surgery, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan, China.
Yaozong
Y
Wang
Department of General Surgery, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan, China.
Li
L
Mei
The Center for Biomedical Research, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan 430022, Hubei Province, China.
Long
L
He
Department of Hematology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan, Hubei, China.
Wen
W
Zeng
The Center for Biomedical Research, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan 430022, Hubei Province, China.
Cong-Yi
CY
Wang
Department of General Surgery, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology Wuhan, China.
Huang
H
Tao
Differentiated thyroid cancer (DTC); MRI; reoperation; ultrasonography