Background: Many papers have reported the results achieved with combined therapy for Ewing's tumors, but little is known about the treatment and outcome of those 30-40% of patients who relapse.
Patients and methods: In a retrospective study, we evaluated 195 patients with Ewing's tumors treated at our institution from 1979 to 1997 with chemotherapy, radiotherapy, surgery or combined therapies after recurrence.
Results: A second complete remission was achieved in only 26 patients (13.3%); 12 relapsed again and died of the tumor. The 5-year post-relapse event-free survival and overall survival were 9.7% and 13.8%, respectively; both of which were significantly better for patients who had relapsed >/=2 years after the beginning of the first treatment (14.3% versus 2.5%; P <0.001) and for patients who relapsed with only lung metastases (14.5% versus 0.9%; P <0.0005). In terms of treatment, patients treated with surgery or radiotherapy, alone or in combination with chemotherapy, had better survival rates than patients treated with chemotherapy alone (15.4% versus 0.9%; P <0.0001).
Conclusions: The outcome of Ewing's tumor patients who relapse after combined treatment is very poor. However, these patients may be divided into two groups: those that can be cured with traditional treatments (late relapse and/or only lung metastases), and a second group of patients (early relapses with metastases in lungs and/or other sites) who gain no benefit from traditional therapies. For the latter group, multicenter studies are needed to evaluate new strategies of treatment.