Abstract

Extraosseous Ewing sarcoma is a rare soft tissue tumour that is histologically indistinguishable from the bone Ewing sarcoma. The translocation involving chromosome 22 along with CD 99 expression is pathognomonic and is useful in differentiating from other small round cell tumours. Primary lung involvement by this malignant tumour is very uncommon and up to this date only ten cases have been reported. We report a further case in a 15 year-old-female who presented with a huge lung mass causing an opaque haemithorax.