Outcomes and prognostic factors for Ewing-family tumors of the extremities.

ABSTRACT

BACKGROUND: There are few published studies describing the clinical results of patients uniformly treated for a Ewing-family tumor of an extremity. METHODS: We performed a review of patients who had received uniform treatment consisting of neoadjuvant chemotherapy, surgery and/or radiation therapy as local treatment, and then adjuvant chemotherapy from June 2003 to November 2011 at a single institution. RESULTS: There were 158 patients included in the study. The median age was fifteen years. Sixty-nine (44%) of the patients had metastatic disease at presentation. Fifty-seven patients underwent surgery, and forty-one received radical radiation therapy following neoadjuvant chemotherapy. After a median of 24.3 months (range, 1.6 to ninety-seven months) of follow-up, the five-year event-free survival, overall survival, and local control rates (and standard error) were 24.1% ± 4.3%, 43.5% ± 6%, and 55% ± 6.8%, respectively, for the entire cohort and 36.4% ± 6.2%, 57.6% ± 7.4%, and 58.2% ± 7.9%, respectively, for patients without metastases. In the multivariate analysis, metastases predicted inferior event-free survival (p = 0.02) and overall survival (p = 0.03) rates in the entire cohort, whereas radical radiation therapy predicted an inferior local control rate in the entire cohort (p = 0.001) and in patients without metastases (p = 0.04). In the group with localized disease, there was no difference between the patients who received radical radiation therapy and those who underwent surgery with regard to tumor diameter (p = 0.8) or post-neoadjuvant chemotherapy response (p = 0.1). A white blood cell count (WBC) of >11 × 109/L predicted inferior event-free survival (p = 0.005) and local control (p = 0.02) rates for patients without metastases. CONCLUSIONS: To our knowledge, this is the largest study on extremity Ewing-family tumors treated with uniform chemotherapy and either surgical resection or radical radiation therapy in Asia. All possible efforts should be made to resect a primary tumor after neoadjuvant chemotherapy, as radical radiation therapy alone results in a poor local control rate despite a good post-neoadjuvant chemotherapy response. Patients without metastases but with a high WBC had inferior event-free survival and local control rates and may require more aggressive therapy. LEVEL OF EVIDENCE Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.