The aim of this study was to determine whether the behaviour of Ewing's sarcoma of bone in adult patients is the same as that observed in children and adolescents. We reviewed the clinical features and outcomes of 23 patients over the age of 39 (17 males, 6 females) who had been treated with neoadjuvant chemotherapy between 1983 and 1995 at our institution. The most common primary sites of tumor were the extremities (16 cases); tumor volume was more than 100 ml in 17 patients, and elevated serum LDH levels were found in 6 cases. The local treatment was surgery in 8 cases, surgery plus radiotherapy in 8, and radiotherapy alone in 7 cases. Chemotherapy comprised a 4-drug regimen in 10 patients, while the other 13 patients received 6 drugs. At a follow-up of 8.8 years (3.5-15) 13 patients remained continuously free of disease and 10 relapsed. The 5-year disease-free survival and overall survival rates were 53% and 59%, respectively. Clinical features, dose intensity, and toxicity of chemotherapy, as well as the outcome of these 23 patients were found to be exactly comparable to the findings observed in 327 patients younger than 40 years treated at our institution in the same period, with the same therapy. We conclude that Ewing's sarcoma of bone in adults is no different from that occurring in children, and we therefore recommend the inclusion of all adult patients in multidisciplinary treatment trials of this tumor.