Figure 2.
A 3-year-old boy with Stage IV neuroblastoma who presented with left hip pain, limp and fever. A blood test showed elevated chronic reactive protein (CRP). He was initially misdiagnosed as having septic arthritis. (a) Plain radiography of both hips shows no obvious bony destruction of the left proximal femur when compared with the asymptomatic right side. (b) Coronal MR T2 weighted image with fat saturation of the left hip reveals marked T2 hyperintense signal of proximal femoral metaphysic and acetablum (white arrows) together with signal change in the surrounding muscle (arrow heads). This was misinterpreted as osteomyelitis at the initial study. (c) MRI of the spine and abdomen shows distal cord and cauda equina compression by a large abdominal soft-tissue mass with intraspinal extension (white arrow). (d) Contrast-enhanced axial CT image shows a large heterogeneously enhancing soft-tissue mass (T) with extensive intratumoural calcifications (white arrow) in the left side abdomen. The left kidney (not shown) is displaced inferiorly and the left renal vein (arrowhead) is encased. Ultrasound biopsy confirmed neuroblastoma.