Toddler with a right-sided abdominal mass

MRI of Wilms tumor
AXR (above left) shows displacement of the bowel out of the right side of the abdomen. Sagittal US of the right kidney (above right) shows a large right renal mass that spares the upper pole of the right kidney. Coronal T1 MRI with contrast of the abdomen (below left) shows a large mass that is heterogenous in appearance that arises from the lower pole of the right kidney and that is demonstrating a claw sign superiorly. Axial T2 MRI (below right) again shows the heterogenous nature of the mass due to hemorrhage and necrosis.

The diagnosis was Wilms tumor.