Intramuscular juvenile xanthogranuloma: sonographic and MR findings.

BACKGROUND

Juvenile xanthogranuloma is a rare benign lesion, most often cutaneous or subcutaneous, and found in infants.

OBJECTIVE

To review the imaging approach to an intramuscular mass in an infant.

METHODS

A case is reported of a 2-month-old boy who presented with a solitary left arm mass which was evaluated with ultrasound and MRI and then biopsied.

RESULTS

Imaging demonstrated a well-defined homogeneous solid mass located in the triceps muscle. The mass was resected and pathology revealed intramuscular juvenile xanthogranuloma.

CONCLUSION

Intramuscular juvenile xanthogranuloma, although extremely rare, has imaging features similar to those of more common malignant tumors of infancy. The imaging findings are nonspecific, but this diagnosis should be considered in the differential of a solid intramuscular mass in an infant.