Role of Diffusion Weighted MRI (DW-MR) in Detection of Satellite Lesions Not Detected with Multiphase CT Scans in Hepatoblastoma and Its Implications for Management

Objective To evaluate the role of diffusion-weighted magnetic resonance imaging (DW-MR) in hepatoblastoma as compared to multiphase contrast enhanced computed tomography (CECT) scans for detection of satellite lesions. Methods In this prospective study on new cases of hepatoblastoma, multiphase CECT scans and DW-MR were performed before initiation of chemotherapy. Results of interpretation were compared for detection of satellite lesions. PRETEXT grouping and risk categorization was done according to SIOPEL based on CECT scan. Results Nine boys and 1 girl with hepatoblastoma, with median age of 11.5 mo were included. All patients were stratified as high-risk group with 2 (20%) in PRETEXT II and 8 (80%) in PRETEXT III. In 2 of 10 (20%) patients, additional satellite lesions were detected on DW-MR, which upgraded their stage. One of the two patients had one satellite lesion identified on CECT, while additional seven satellite lesions were identified on DW-MR imaging. For the other patient, CECT showed no satellite lesion while DW-MR detected six satellite lesions. Conclusion MRI has become the gold standard investigation for evaluation of hepatoblastoma. DW-MR, which is a contrast free technique, is a better tool for assessment of satellite lesions which are usually missed on CECT. This would help in proper staging, planning of management and prognostication.