Diagnostic Values of CEUS, CECT and CEMRI for Renal Cystic Lesions on the Current Bosniak Criterion-A Meta-analysi

Objective: CT-based Bosniak classification system has been routinely used to assess complex renal cystic lesions and also been applied to contrast-enhanced magnetic resonance imaging (CEMRI) and contrast-enhanced ultrasound (CEUS). Besides, the 2019 new version incorporated MRI into the Bosniak system. However, the role of US in the Bosniak system has not been clearly established. The aim of this study was to compare the diagnostic ability of CEUS, CECT and CEMRI for renal cystic lesions based on the current Bosniak classification. Methods: Related studies were searched in PubMed, EMBASE, and the Cochrane Library databases from January 1, 2010 to December 14, 2020. QUADAS-2 was used to assess the study quality. Meta-analysis was performed by "midas modules" of Stata SE 15.0 software. The bivariate mixed-effect model was used. The pooled sensitivity and specificity of these three modalities were calculated and compared. Meta-regression and subgroup analyses were conducted to reveal the source of heterogeneity. Results: CEUS showed highest pooled sensitivity and specificity, which were 98% (95% CI: 91%, 100%) and 80% (95% CI: 64%, 90%) respectively. Pooled estimates of CEMRI were slightly lower than those of CECT with the sensitivity 85% (95% CI: 77%, 91%) versus 88% (95% CI: 77%, 94%) and specificity 71% (95% CI: 52%, 85%) versus 79% (95% CI: 70%, 86%), respectively. Conclusions: Based on the current Bosniak classification, CEUS seemed superior to CECT and CEMRI for the diagnosis of complex renal cystic masses, and could serve as a valuable alternative for CECT and CEMRI.