Real-time ultrasound elastography: an assessment of enlarged cervical lymph nodes

Abstract

Objectives

To determine the efficacy of real-time elastography (RTE), compared with our previously proposed prediction model, in the detection of malignancy in cervical lymph nodes (LNs).

Methods

One hundred and thirty-one patients underwent ultrasound-guided fine needle aspiration biopsy (ultrasound FNAB) after ultrasound and RTE evaluation. The formula of the RTE scoring system was a four-point visual scale, based on a previously determined model. The formula of the prediction model was: $0.06\times \left( {\mathrm{age}} \right)+4.76\times \left( {{{{\mathrm{short}-\mathrm{axis}}} \left/ {{\mathrm{long}-\mathrm{axis}\;\mathrm{ratio}}} \right.}} \right)+2.15\times \left( {\mathrm{internal}\;\mathrm{echo}} \right)+1.80\times \left( {\mathrm{vascular}\;\mathrm{pattern}} \right)$. An extended model was constructed with four previous predictors and elasticity scores, using a logistic regression model.

Results

Final histology revealed 77 benign and 54 malignant LNs. In the elasticity score system, sensitivity was 66.7 %, specificity was 57.1 %, the positive predictive value (PPV) was 52.2 % and the negative predictive value (NPV) was 71.0 %. In the prediction model system, sensitivity was 79.6 %, specificity was 92.2 %, the PPV was 87.8 % and the NPV was 86.6 %. When the extended and the original model were compared, the areas under the receiver operating characteristic curve (c-statistic) was 0.94 and 0.95, respectively (P > 0.05).

Conclusions

Qualitative RTE offers no additional value over conventional ultrasound in predicting malignancy in cervical LNs.

Key Points

• An ultrasound system can help in the assessment of cervical lymph nodes.

• Grey-scale and power Doppler ultrasound remain fundamental for neck nodal evaluation.

• Qualitative real-time elastography provided no additional value compared with current prediction models.