Systematic review and meta-analysis: diagnostic value of different ultrasound for benign and malignant thyroid nodules

Abstract

Background: Conventional ultrasound and contrast-enhanced ultrasound (CEUS) are commonly used in the diagnosis of benign and malignant thyroid nodules. However, the value of the two methods in the diagnosis of benign and malignant thyroid nodules remains controversial.

Methods: PubMed, Medline, EBSCO, Science Direct, Cochrane Library, China National Knowledge Infrastructure (CNKI) database and manual journal retrieval were searched from January 2000 to January 2022, to include research on conventional ultrasound or CEUS in the diagnosis of benign and malignant thyroid nodule related clinical studies. Meta-analysis was conducted using RevMan5.3 and Stata Corp to analyze the sensitivity and specificity of conventional ultrasound and CEUS in the diagnosis of benign and malignant thyroid nodules with 95% confidence interval (CI) as indicators. Heterogeneity of the results was evaluated by Q test and I² in RevMan5.3. Deek's method was used to evaluate publication bias.

Results: A total of 1,378 nodules were included in 11 literatures, including 535 malignant thyroid nodules and 843 benign thyroid nodules. Heterogeneity tests conducted for CEUS diagnostic sensitivity of the 6 included literatures indicated that there was no heterogeneity among the study groups [Q=2.05, degree of freedom (df) =5.00, I²=0.00%, P=0.84]. The combined sensitivity was 0.87, with 95% confidence interval (CI): 0.82 to 0.90. Heterogeneity tests on the diagnostic specificity of CEUS of the six included literatures suggested that there was heterogeneity among the different study groups (Q=14.27, df =5.00, I²=64.96%, P=0.01). The combined specificity was 0.84 (95% CI: 0.78 to 0.89). Heterogeneity tests performed on the sensitivity of five conventional ultrasound diagnosis articles revealed that there was heterogeneity among different study groups (Q=13.62, df =4.00, I²=70.64%, P=0.01). The combined sensitivity was 0.86 (95% CI: 0.78 to 0.92). Heterogeneity tests on the specificity of conventional ultrasound diagnosis in five included literatures indicated that there was heterogeneity among different study groups (Q=16.94, df =4.00, I²=76.39%, P=0.00). The combined specificity was 0.84 (95% CI: 0.75 to 0.90). There was no bias in the included literature.

Discussion: The sensitivity of CEUS in the diagnosis of benign and malignant thyroid nodules was slightly higher than that of conventional ultrasound, which provides a reference for the clinical diagnosis of benign and malignant thyroid nodules.

Keywords: Thyroid nodule; contrast-enhanced ultrasound (CEUS); conventional ultrasound; diagnosis; meta-analysis.

Figure 1

The document retrieval process.

Figure 2

The evaluation chart of risk bias in the included literature.

Figure 3

A summary diagram of the risk bias evaluation of the included literature.

Figure 4

A forest plot showing the sensitivity and specificity of individual and aggregate CEUS studies. CI, confidence interval; df, degree of freedom; CEUS, contrast-enhanced ultrasound.

Figure 5

The SROC curve of CEUS. SROC, summary receiver operating characteristic; CEUS, contrast-enhanced ultrasound; AUC, area under curve; SENS, sensitivity; SPEC, specificity.

Figure 6

A forest plots showing the sensitivity and specificity for individual and aggregate studies of conventional ultrasound. CI, confidence interval; df, degree of freedom.

Figure 7

The SROC curve of conventional ultrasound. SROC, summary receiver operating characteristic; AUC, area under curve; SENS, sensitivity; SPEC, specificity.