Presentation
Recent cough. No breathlessness. Normal O2 saturations. Has complained of some left sided shoulder pain.
Patient Data
Lungs are well expanded and clear. Normal heart and mediastinal contours.
Abnormality centred on the left scapula with permeative appearance and bone destruction.
The abnormality at the left scapula is confirmed and clearly seen as a large soft tissue mass arising from the scapula and extending posteriorly between the scapular spine and the coracoid. Proximal humerus appears normal.
Permeative bone destruction of the medial portion of the left scapula. Glenoid spared. Normal proximal humerus.
Postoperative appearance with removal of scapula. Left sided dual-lumen port-a-cath.
Microscopy
Cores of tissues containing tumour.
Characterised by small round blue cells with a monomorphic appearance.
Prominent vascular pattern with some large vessels.
Fragment of necrotic tumour.
No differentiation.
In some fragments, tumour invades soft tissue.
No bone present. No osteoid formation.
CD99 - positive
Desmin - negative
myo-D1 - negative
myogen - negative
CD45, panCK, S100, PGP9.5, WT1 and ERG - all negative.
Overall appearances of a small round blue cell tumour without differentiation. Most in keeping with a Ewing sarcoma.
Case Discussion
Bone tumours in children can present incidentally, often after trauma. Where a tumour arises from a flat bone (scapula, pelvis, rib) and there is a significant soft tissue mass, consider Ewing sarcoma high up the differential.