Diagnostic accuracy of DWI in patients with ovarian cancer: A meta-analysis

Abstract

Background: Diffusion weighted imaging (DWI) is recently developed for identifying different malignant tumors. In this article the diagnostic accuracy of DWI for ovarian cancer was evaluated by synthesis of published data.

Methods: A comprehensive literature search was conducted in PubMed/MEDLINE and Embase databases on the diagnostic performance of DWI for ovarian cancer published in English. Methodological quality was evaluated following Quality Assessment for Studies of Diagnostic Accuracy 2 (QUADAS 2) tool. We adopted the summary receiver operating characteristic (SROC) curve to assess the DWI accuracy.

Results: Twelve studies including 1142 lesions were analyzed in this meta-analysis to estimate the pooled Sen (sensitivity), Spe (specificity), PLR (positive likelihood ratio), NLR (negative likelihood ratio), and construct SROC (summary receiver operating characteristics) curve. The pooled Sen and Spe were 0.86 (95% confidence interval [CI], 0.83-0.89) and 0.81 (95%CI, 0.77-0.84), respectively. The pooled PLR and pooled NLR were 5.07 (95%CI, 3.15-8.16) and 0.17 (95%CI, 0.10-0.30), respectively. The pooled diagnostic odds ratio (DOR) was 35.23 (95%CI, 17.21-72.14). The area under the curve (AUC) was 0.9160.

Conclusion: DWI had moderately excellent diagnostic ability for ovarian cancer and promised to be a helpful diagnostic tool for patients of ovarian cancer.

Figure 1

Flow chart of selection process for eligible studies.

Figure 2

Forest plot of sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of DWI for detection of ovarian cancer. Solid circles represent the study-specific point estimates of sensitivity, specificity, positive LR, and negative LR. Horizontal lines indicate 95% confidence interval (CI). The diamond represents the pooled estimates and 95% CI. DWI = diffusion weighted imaging, LR = likelihood ratio.

Figure 3

Forest plot of DOR of DWI for detection of ovarian cancer. Solid circles represent the study-specific DOR. Horizontal lines indicate 95% confidence interval (CI). The area of solid circles reflects the study specific weight. The diamond represents the pooled DOR and 95% CI. DOR = diagnostic odds ratio, DWI = diffusion weighted imaging.

Figure 4

The summary receiver operating characteristic (SROC) curve and Q∗ index of diagnostic performance of DWI in evaluation of ovarian cancer. Solid circles represent each study included in the meta-analysis. The size of each study is indicated by the size of the solid circle. The regression SROC curves summarize the overall diagnostic accuracy. DWI = diffusion weighted imaging.

Figure 5

Funnel graph to assess risk of publication bias among included studies. The funnel graph plots the log of the diagnostic odds ratio (DOR) against the standard error of the log of the DOR (an indicator of sample size). Solid circles represent each study in the meta-analysis. Regression line is shown.