Neuroblastoma with bone metastases

The main diagnostic consideration for this case is metastatic neuroblastoma, with a retroperitoneal primary. In isolation, the diffuse marrow infiltration may be seen in leukaemia such as ALL, however, this would not account for the retroperitoneal mass.

Further investigation involves CT/MRI of the chest, abdomen and pelvis, MIBG and correlation with urinary catecholamines.

In In this case, neuroblastoma was confirmed on histology.

Case contributed by Dr Kieran Frawley.

XR demonstrates anAn ill defined-defined region of lucency in the left femoral neck and proximal femoral shaft. On the oblique projection, there is an ill distinct-distinct margin of the posterior femoral cortex.  

MR demonstrates diffuse marrow signal abnormality, with widespread T1 hypointensity, STIR hyperintensity, and heterogeneous enhancement post contrast enhancement. The extent of marrow abnormality is much more than appreciated on x-ray.

There are some regions of enhancing periosteal reaction (i.e. right proximal femur). No visible joint effusions. The muscles and soft tissues of the lower limbs are normal. At the edge of the film, best seen on the axial T1 FS post contrast sequences, there is a partially imaged lobulated lesion in the right suprarenal region. The right kidney is displaced inferiorly, and the IVC/aorta are splayed.