Diagnostic Accuracy of Diffusion-Weighted Imaging in Differentiation of Serous Cystadenomas and Mucinous Cystic Neoplasms

Purpose. To evaluate the incremental value of diffusion-weighted imaging (DWI) in relation to conventional magnetic resonance imaging (MRI) in the differentiation of serous cystadenomas (SCAs) and mucinous cystic neoplasms (MCNs) at 3.0 T. Methods. This retrospective study included 24 patients with SCAs and 39 patients with MCNs which were proved pathologically. All patients underwent conventional MRI and DWI examinations at 3.0 T. Imaging features, apparent diffusion coefficient (ADC) values, and normalized ADC between SCAs and MCNs were compared and placed in multivariate models to predict the differential diagnosis of SCAs and MCNs. The optimal cut-off value was determined using a receiver operating characteristic curve. Results. There are significant differences between SCAs and MCNs with respect to tumor location, shape, and morphology (P = 0.017, P < 0.001, and P < 0.001, respectively). ADC values and normalized ADC of SCAs were significantly lower than those of MCNs (P < 0.001 and P = 0.005, respectively). The addition of the ADC value to imaging features improved the diagnostic performance of DWI MR imaging: the area under the receiver operating characteristic curve increased from 0.907 to 0.972 (P = 0.0314). Conclusions. This indicates that DWI with ADC value assessment may improve the differentiation of SCAs over MCNs beyond the level of characterization achieved with conventional MRI at 3.0 T.