PRIMARY EMBRYONAL RHABDOMYOSARCOMA OF LONG-BONE - CASE-REPORT AND REVIEW OF THE LITERATURE

We report a case of primary embryonal rhabdomyosarcoma of long bone, p resenting as a lytic destructive bone tumor in the right femoral diaph ysis of a 7-year-old girl. To our knowledge, this is only the third re port of this entity. The neoplasm was a pure embryonal rhabdomyosarcom a with numerous rhabdomyoblasts. Immunohistochemistry confirmed the di agnosis: The cells were reactive with antibodies directed against desm in, muscle-specific actin, and myoglobin. No other neoplastic mesenchy mal component was present within the tumor. Although rare, primary rha bdomyosarcoma, along with Ewing's tumor and osteosarcoma, should be co nsidered in the differential diagnosis of malignant bone tumors in chi ldhood.