Usefulness of Apparent Diffusion Coefficient of Diffusion- Weighted Imaging for Differential Diagnosis of Primary Solid and Cystic Renal Masses

Abstract

SummaryBackgroundTo evaluate the value of diffusion-weighted imaging (DWI) for distinguishing between benign and malignant renal masses.Material/MethodsSeventy-five patients with 75 unilateral renal lesions were included, and 75 normal contralateral kidneys served as controls. The lesions were categorized into four groups as malignant cystic, malignant solid, benign cystic and benign solid. The apparent diffusion coefficients (ADCs) were evaluated for two different b values (b=600 s/mm2 and b=1000 s/mm2). Receiving operating characteristic analysis was performed to identify threshold ADCs.ResultsSensitivity and specificity were 67% and 77% (p=0.003) at the cutoff value of 1.5 for b=600 s/mm2, and 79% and 62% (p=0.004) at the cutoff value of 1.99 for b=1000 s/mm2 as regards the differentiation between solid benign and malignant renal lesions. Sensitivity and specificity were 78% and 79% (p=0.001) at the cutoff value of 3.1 for b=600 s/mm2, and 86% and 61% (p=0.003) at the cutoff value of 2.9 for b=1000 s/mm2 as regrads the differentiation between benign and malignant cystic renal lesions.ConclusionsDWI can be an effective diagnostic method for distinguishing between benign and malignant renal masses.

Comparison of Diagnostic Medical Sonography, Computed Tomography, Magnetic Resonance Imaging, and Contrast-Enhanced Ultrasound in the Investigation of Renal Lesions

“…10 MRI offers high contrast resolution, shows detailed characteristics of soft tissues, and provides triplanar images. 13 It is very useful for those who are not candidates for CT, such as in patients with an allergy to iodine or who are pregnant.…”

“…14 Diffusion-weighted imaging (DWI) MRI can be an effective method for distinguishing between benign and malignant renal lesions of solid or cystic nature. 13 DWI is a fast, noninvasive method that does not use a contrast agent. This technique is based on the movement of water molecules across tissues.…”

“…DWI and the apparent diffusion coefficient (ADC) may provide additional diagnostic information compared with that obtained by conventional MRI alone. 13 The role of DWI MRI as a biomarker for the investigation of benign or malignant renal masses, subtypes of RCC, and histological grades is under evaluation. 7 There are several strengths and limitations to the use of MRI.…”

Role of Diffusion-Weighted MR Imaging in Characterization of Retro-Peritoneal Fibrosis and Differentiating it from Malignant Neoplasms

“…Diffusion-weighted imaging (DWI) is a noninvasive method that is based on the movement of water molecules across tissues. DWI and the apparent diffusion coefficient (ADC) may provide additional information to that obtained from conventional MRI [17] . DWI can contribute to differentiate between active and chronic (inactive) RPF as well as between benign RPF and malignant neoplasms with RPF morphology [18] .…”