Ewing's sarcoma family tumors mimicking primary central nervous system neoplasms.

Ewing's sarcoma family tumors (ESFTs) and embyronal tumors of the central nervous system are malignant primitive neuroectodermal tumors (PNETs) that can arise in the central nervous system, bones, or soft tissues. When ESFTs involve the central nervous system or nearby structures the diagnosis depends on cytogenetics and immunohistochemistry as these tumors can appear otherwise histologically identical to central PNETs. Correct diagnosis is essential as the treatment paradigms for both entities differ. We present two cases of isolated central nervous system presentations of ESFTs mimicking primary central nervous system neoplasms.