Bone marrow biopsy is a routine part of the staging workup for Ewing’s sarcoma, and is not routinely obtained for staging of osteosarcoma.
Ewing’s is a small round cell (blue cell) tumor that occurs most commonly in children and young adults. Clinical presentations of these tumors frequently mimic infection with low grade fever, elevated white counts and high markers of inflammation. The radiographic appearance will show a large lytic lesion in the metaphysis or diaphysis. Reactive periosteum may be lifted off the bone in multiple layers, termed “onion skinning” which is characteristic but uncommon. Bone marrow biopsy is done because Ewing's sarcoma can metastasize via the marrow.
Carvajal et al report the Ewing's sarcoma family of tumors (EFT) includes ES of bone (ESB), extraosseous ES (EES), peripheral primitive neuroectodermal tumor of bone (pPNET), and malignant small-cell tumor of the thoracopulmonary region, or Askin's tumor, all of which are now known to be neoplasms of neuroectodermal origin.
Menendez LR (ed): Orthopaedic Knowledge Update: Musculoskeletal Tumors. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 21-27.
Gorlick RG Toretsky JA, Marina N, et al: Bone tumors. In Kufe DW, Pollock RE, Weichselbaum RR, et al (eds): Cancer Medicine 6. Hamilton, BC, Decker, 2003, pp 2388-2392.
Carvajal R, Meyers P. Ewing's sarcoma and primitive neuroectodermal family of tumors. Hematol Oncol Clin North Am. 2005 Jun;19(3):501-25, vi-vii. Review. PubMed PMID: 15939194.
PMID:15939194 (Link to Abstract)