title: Establishing long-term survival and cure in young patients with Ewing's sarcoma.
abstract: This paper investigates the potential for long-term survivorship for young patients diagnosed with Ewing's sarcoma. Data are examined from two successive UKCCSG Ewing's Tumour studies (ET-1 and ET-2). Patients have been followed for up to 20 years. These studies had suggested that better 5-year survival with ET-2 over the earlier ET-1 was achieved by replacing cyclophosphamide by ifosfamide and increasing the dose of doxorubicin in a four-drug chemotherapy regimen. The updated hazard ratio, stratified for metastatic status at diagnosis, of 0.39 (95% confidence interval 0.12-0.61) confirmed the advantage of the ET-2 regimen in terms of overall survival. Cure models, based on the Weibull distribution, suggested that factors for long-term survival in addition to presence of metastases were age, primary site of tumour and study. Modelling identified the proportion cured with the ET-2 protocol as best at 70% in those who are under 10 years with a nonpelvic primary site and without metastatic disease. This contrasts to only 13% cure in those with the corresponding adverse prognostic indicators. Additionally, the risk of death remains greatest but relatively constant over the first 2 years postdiagnosis, and then declines to a lower but constant value for the next 3 years before reaching the 'cure plateau' at about 5 years. This investigation suggests that 'cure' is possible for patients with Ewing's sarcoma. This is established at approximately 5 years post diagnosis and the proportion cured depends on the presence of metastases, pelvic site and age at diagnosis.
authors.affiliation: UKCCSG, University of Leicester, Leicester, UK. clw19@leicester.ac.uk
authors.forename: C L
authors.initials: CL
authors.lastname: Weston
authors.forename: C
authors.initials: C
authors.lastname: Douglas
authors.forename: A W
authors.initials: AW
authors.lastname: Craft
authors.forename: I J
authors.initials: IJ
authors.lastname: Lewis
authors.forename: D
authors.initials: D
authors.lastname: Machin
mesh_terms: D000293:Adolescent; D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008297:Male; D010386:Pelvic Neoplasms / Q000188:drug therapy* / Q000401:mortality* / Q000473:pathology; D012512:Sarcoma, Ewing / Q000188:drug therapy* / Q000401:mortality* / Q000556:secondary; D015996:Survival Rate; D017741:Survivors