Prognostic significance of histopathologic response to chemotherapy in nonmetastatic Ewing's sarcoma of the extremities.

Abstract

This new histopathologic analysis technique for the evaluation of neoadjuvant chemotherapy effectiveness (which does not rely on tumor volume for its assessment) is a valuable prognostic indicator for patients with Ewing's sarcoma treated with surgery. Based on this preliminary report, cases of grade I or II chemotherapeutic tumor response should be considered clinical failures and a different, more aggressive postoperative chemotherapy regimen should be considered.