Ultrasound Elastography in the Diagnosis of Malignant Cervical Lymphadenopathy in Children: Can It Replace Surgical Biopsy?

Diagnostic Performance of Ultrasound for Differentiating Malignant From Benign Cervical Lymphadenopathy in Children: A Systematic Review and Meta-Analysis

OBJECTIVES

To evaluate the diagnostic performance of ultrasound (US) features used to differentiate malignant from benign cervical lymphadenopathy in children.

METHODS

PubMed and EMBASE were searched for articles reporting the diagnostic performance of US features to differentiate benign and malignant cervical lymphadenopathy in children. Article quality was evaluated using the QUADAS-2 tool. Sensitivity and specificity were pooled using a bivariate random-effects model. Further sensitivity analyses and meta-regression were performed to determine the potential source of heterogeneity. The area under the receiver operating characteristic curve was calculated using the hierarchical summary receiver operating characteristic model.

RESULTS

Ten articles (1077 children) were included. Among the retrieved US features, abnormal vascularity, heterogeneous echogenicity, abnormal hilum echogenicity, and long-axis/short-axis (L/S) ratio were significantly associated with malignant lymphadenopathy, with pooled diagnostic odds ratios of 36 (95% confidence interval [CI]: 14-92), 17 (3-91), 16 (5-54), and 7 (5-9), respectively. The most sensitive US features were abnormal hilum echogenicity (0.86, 95% CI: 0.66-0.95) and heterogeneous echogenicity (0.84, 95% CI: 0.25-0.99). Abnormal vascularity (0.91, 95% CI: 0.82-0.97) was the most specific. Substantial heterogeneity was found in both sensitivity and specificity (I2 > 50%; P < .01), although the source was not revealed.

CONCLUSION

Among US features, abnormal vascularity, heterogeneous echogenicity, abnormal hilum echogenicity, and L/S ratio are useful for differentiating malignant from benign cervical lymphadenopathy in children, showing good diagnostic performance. These findings should be carefully interpreted due to unexplained heterogeneity, which may lower the validity of the pooled estimates.

Back to the basics-risk factor identification of pediatric malignant lymphadenopathy proven by pathological studies

PURPOSE

Lymphadenopathy (LAP) is a common problem in the pediatric patient. History, physical examinations (PE), ultrasounds, and blood tests were often obtained while studying such lesions. Malignancy should be highly suspected in certain conditions. This study evaluates the relationship between malignant LAP and risk factors for pediatric patients.

MATERIALS AND METHODS

Medical records of matched patients are reviewed, and data are retrospectively collected. History, PE findings, laboratory data, ultrasound findings, and pathological findings were recorded and analyzed. The median values (interquartile range, IQR) were expressed for continuous variables, and the number of patients (percentage) for categorical variables. Comparisons between groups were performed using the Mann-Whitney U test and the chi-squared test. The significance was set as p value < 0.05.

RESULTS

A total of 142 pediatric patients underwent a biopsy in our department for LAP from July 2004 to August 2021. Among them, 108 (76.1 %) patients had benign lesions, and 34 (23.9 %) had malignancies. Weight loss, fixed LAP, firm consistency, and serum lactate dehydrogenase (LDH) exceeding 240 U/L were more related to malignant LAP than other risk factors. Multiple regression analysis revealed two independent risk factors. The receiver operating characteristic curve regarding LDH level predicting malignancy revealed a sensitivity of 79.31 % and specificity of 36.51 % by applying the criterion as 230 U/L.

CONCLUSIONS

For pediatric LAP, history-taking and physical examinations remained the most important approaches. Ultrasounds, serum LDH, and other laboratory studies may only provide clues. The cutoff level of LDH revealed low sensitivity and specificity for malignant LAP. With firm LAP, which is fixed, a biopsy for tissue proof should be performed.

Ultrasound Elastography in Children

Ultrasound elastography is a novel ultrasound technique, being extensively researched in children in the last decade. It measures tissue elasticity with the observation of tissue response after an external stimulus. From research to clinical practice, ultrasound elastography has evolved significantly in liver fibrosis evaluation in children; however, several other applications of the technique are available in both clinical practice and research environments. Practically, in children any organ can be assessed, including the brain in early ages, along with muscle and connective tissue elasticity evaluation, spleen, kidney, skin, lymphatic tissue, etc. The elastography method, age, body mass index and technical points should be considered when performing ultrasound elastography. This review highlights its vast potential as a diagnostic tool in the pediatric population, where ultrasound is a dominant imaging tool; however, the indications and exam protocol for its clinical use in several fields in pediatrics have yet to be elucidated.

Ultrasound elastography in children - nice to have for scientific studies or arrived in clinical routine?

Ultrasound elastography (USE) is a modality that in addition to fundamental B-mode, Doppler, and contrast-enhanced sonography is suitable to make qualitative and quantitative statements about the stiffness of tissues. Introduced more than 20 years ago in adults, USE becomes now a diagnostic tool also in children. The aim of this paper is to describe current available techniques for USE in children. The significance for routine use in children is shown, and further interesting applications are reported.

Preliminary study of sound touch elastography in diffuse thyroid disease in children

OBJECTIVE

The purpose of this study was to evaluate the use of sound touch elastography (STE) in conjunction with conventional ultrasound in the differential diagnosis of diffuse thyroid disease (DTD) and normal thyroid in children.

METHODS

Studies performed on 62 children with DTD and 30 normal volunteers were reviewed. Standard gray scale ultrasound, Doppler ultrasound and STE of the examinees, and the serum test results of children with DTD were collected, analyzed and compared.

RESULTS

The STE-Mean values in the Graves' disease (GD) group, Hashimoto's thyroiditis (HT) group, and normal control group, respectively, were 19.35 ± 5.00 kPa, 19.43 ± 6.06 kPa, and 11.24 ± 1.99 kPa. With an area under the ROC curve (AUC) of 0.945, STE-Mean values differentiated DTD from normal children. The peak systolic velocity (PSV) of the superior thyroid artery separated DTD from normal children and AUC from children with GD and HT, respectively, and was 0.992 and 0.864. The PSV of superior thyroid artery revealed a somewhat favorable connection with FT3 and FT4.

CONCLUSION

The STE results revealed that thyroid stiffness was higher in children with DTD than in normal children, but further differentiation into GD and HT subgroups lacked specificity, and the superior thyroid artery flow velocity might be a good supplement to distinguish both.