From January 1988 to October 1991, one hundred and twelve patients with non metastatic Ewing's sarcoma of bone were treated with a 6 drugs neoadjuvant chemotherapy protocol (IOR/Ew2) in which, to the four drugs usually used in the treatment of this tumor (vincristine, adriamycin, cyclophosphamide and dactinomycin), Ifosfamide and VP-16 were added. The local treatment consisted of radiation therapy in 52 cases, a surgical treatment was performed in 27 cases and in the remaining 33 cases both the previous treatments were used. At a mean follow-up of 4.5 years (3-6.5), 62 patients (55.3%) remained continuously free of disease and 50 relapsed: 41 with metastases, 8 with mestastases and local recurrence and 1 with local recurrence alone. These results do not differ from the ones obtained in our Institution in 98 patients treated between 1983 and 1988 with a neoadjuvant protocol (IOR/Ew1) in which only VCR, ADM, CTX and actD were used (3 year CDFS: IOR/Ew2 = 60.7%-IOR/Ew1 = 55.1%). In IOR/Ew2 a higher DFS rate was observed in the patients with tumor located in the axile bones in comparison with that obtained in the previous study (IOR/Ew2 = 48.6%, IOR Ew1 = 25.6%). Despite the fact that these results came from a not-randomized study, the authors conclude that the addition of Ifosfamide and VP-16 to the four drugs standard regimen do not improve the outcome of patients with Ewing's sarcoma of bone, with the possible exception of the patients with tumor located in the axile bones. This data should be confirmed in further and larger studies.