Presentation
Painless swelling of the right paravertebral region, rapidly increasing in size.
Patient Data
Well-encapsulated right paravertebral mass probably of intermuscular location, measuring 130 x 55 x 25 mm of high signal on T1 and T2, attenuated on fat sat sequences with thin enhanced septae.
Left hemivertebra fused with L1 vertebra (block vertebra)
Case Discussion
The patient's age and the MRI features are suggestive of a lipoblastoma.
Lipoblastoma is a rare, benign, encapsulated tumor that arises from embryonic white fat with more than 90% seen before the age of 3 years.
The imaging features are non-specific but usually seen as a predominantly fatty mass with well-defined margins. It may have myxoid components that predominate and that can also be enhancing.
The main differential diagnosis is liposarcoma, which is extremely rare in children under age 10 years.