Diffusion-Weighted Magnetic Resonance Imaging in the Evaluation of Wilms Tumors: Correlation with Histological Data. Pilot Study

The aim of the study is to assess the difference in apparent diffusion coefficient (ADC) values depending on the degrees of malignancy of Wilms’ tumor. The study includes 64 patients with verified Wilms tumor after a course of chemotherapy, before undergoing surgical treatment. The patients were examined using scanners with magnetic field induction of 3.0 and 1,5 T. ADC data collection (mm2/s) was carried out using specialized software. Statistical analysis was performed using the Graphpad Prism software package. Based on the results of this study, average ADC values were obtained for histological types of Wilms’ tumors distributed by clinical risk groups: 0.4 × 10-3 mm2/s — for the low grade of malignancy, 1.1 × 10-3 mm2/s — for the average grade of malignancy and 0.6 × 10-3 mm2/s — for the high grade. In addition, for the average grade of malignancy, the ADC values were divided into groups depending on the cellular composition — 1 ± 0.2 × 10-3 mm2/s — for the regressive and mixed type; 0.9 ± 0.2 × 10-3 mm2/s — for the epithelial type; 1.3 ± 0.4 × 10-3 mm2/s — for the stromal type. Thus, diffusion-weighted MRI can be a useful tool in the initial assessment and differential diagnosis of patients with Wilms tumor.