New publication by Ben Littenberg

AJR Am J Roentgenol. 2015 Aug;205(2):317-24. doi: 10.2214/AJR.14.13930.

DWI for Renal Mass Characterization: Systematic Review and Meta-Analysis of Diagnostic Test Performance.

Kang SK1,2, Zhang A3, Pandharipande PV4,5, Chandarana H1, Braithwaite RS2,6, Littenberg B7.

Abstract

OBJECTIVE:

The objective of our study was to perform a systematic review and meta-analysis of the test performance of DWI in the characterization of renal masses.

MATERIALS AND METHODS:

We performed searches of three electronic databases for studies on renal mass characterization using DWI. Methodologic quality was assessed for each study. We quantitatively analyzed test performance for three clinical problems: first, benign versus malignant lesions; second, clear cell renal cell carcinoma (RCC) versus other malignancies; and, third, high-versus low-grade clear cell RCCs. We summarized performance as a single pair of sensitivity and specificity values or a summary ROC curve.

RESULTS:

The studies in the literature were limited in both quantity and quality. For classification of benign versus malignant lesions, four studies with 279 lesions yielded a single summary estimate of 86% sensitivity and 78% specificity. For differentiation of clear cell RCC from other malignancies, five studies showed marked heterogeneity not conducive to meta-analysis. For differentiation of high-from low-grade clear cell RCCs, three studies with 110 lesions showed a threshold effect appropriate for summary ROC construction: The AUC was 0.83.

CONCLUSION:

Evidence suggests moderate accuracy of DWI for the prediction of malignancy and high-grade clear cell cancers, whereas DWI performance for ascertaining clear cell histologic grade remains unclear. To develop DWI as a noninvasive approach for the evaluation of solid renal masses, prospective studies with standardized test parameters are needed to better establish DWI performance and its impact on patient outcomes.