Allogeneic and autologous stem-cell transplantation in advanced Ewing tumors

Background:An update of results from the High Risk Protocol ofthe Meta-EICESS Study, conducted at the Pediatric Stem-Cell Transplant Centersof Düsseldorf and Vienna. In order to evaluate a possible therapeuticbenefit after allogeneic SCT in patients with advanced Ewing tumors (AET), wecompared outcome after autologous and allogeneic stem-cell transplantation(SCT).Patients and methods:We analyzed 36 patients treated with themyeloablative Hyper-ME protocol (hyperfractionated total body irradiation,melphalan, etoposide ± carboplatin) between November 1986 and December1994. Minimal follow-up for all patients was five years. All patientsunderwent remission induction chemotherapy and local treatment beforemyeloablative therapy. Seventeen of thirty-six patients had multifocal primaryEwing's tumor, eighteen of thirty-six had early, multiple or multifocalrelapse, one of thirty-six patients had unifocal late relapse. Twenty-six ofthirty-six were treated with autologous and ten of thirty-six with allogeneichematopoetic stem cells. We analyzed the following risk factors, that couldpossibly influence the event-free survival (EFS): number of involved bones,degree of remission at time of SCT, type of graft, indication for SCT, bonemarrow infiltration, bone with concomitant lung disease, age at time ofdiagnosis, pelvic involvement, involved compartment radiation,histopathological diagnosis.Results:EFS for the 36 patients was 0.24 (0.21) ± 0.07.Eighteen of thirty-six patients suffered relapse or died of disease, nine ofthirty-six died of treatment related toxicity (DOC). Nine of thirty-sixpatients are alive in CR. Age 17 years at initial diagnosis (P< 0.005) significantly deteriorated outcome. According to the type ofgraft, EFS was 0.25 ± 0.08 after autologous and 0.20 ± 0.13after allogeneic SCT. Incidence of DOC was more than twice as high afterallogeneic (40%) compared to autologous (19%) SCT, even thoughthe difference did not reach significance (P = 0.08, Fisher's exacttest).Conclusions:Because of the rather short observation period,secondary malignant neoplasm (SMN) may complicate the future clinical courseof some of our patients who are currently viewed as event-free survivors. EFSin AET is not improved by allogeneic SCT due to a higher complication rate.The patient group was to small to analyze for a possiblegraft-versus-tumor effect.