Diffusion weighted imaging in differentiating malignant and benign neuroblastic tumors.

Abstract

Our aim was to assess diffusion weighted imaging (DWI) of neuroblastic tumors and whether apparent diffusion coefficient (ADC) value may have a role in discrimination among neuroblastoma, ganglioneuroblastoma and ganglioneuroma. The DWIs (b=0-800s/mm(2)) of 24 children (13 girls, 11 boys) who were diagnosed neuroblastic tumors on histopathological examination (neuroblastoma=15, ganglioneuroblastoma=5, ganglioneuroma=4) were evaluated retrospectively. The ADC maps were performed by drawing freehand ROI on PACS (Sectra Workstation IDS7, Linköping, Sweden). We observed a significant decrease in ADC value of neuroblastomas 0.869±0.179×10(-3) mm(2)/s compared to ganglioneuroblastomas 0.97±0.203×10(-3) mm(2)/s and ganglioneuromas 1.147±0.299×10(-3) mm(2)/s (p=0.026). There was no significant difference in between ganglioneuroblastoma and ganglioneuroma (p=0.16). In detecting neuroblastomas; the sensitivity, specificity, negative and positive predictive values of ADC were 74, 67, 78.6, 66% respectively with a cut-off value of 0.93×10(-3) mm(2)/s. Our study stands out as the most comprehensive study with larger sample size on this topic. Moreover, we are able to suggest a cut-off value which can discriminate neuroblastoma from ganglioneuroblastoma and ganglioneuroma. We believe that ADC will evolve to an objective, quantitative measurement in discrimination among malignant and benign neuroblastic tumors.