Effect of once-a-day fractionated total body irradiation on the risk of relapse after non-T-cell-depleted HLA-matched sibling transplantation

Purpose. The aim of this study was to assess the impact of fractionated total body irradiation (F-TBI) on treatment-related mortality (TRM) and relapse in patients who received a non-T-cell-depleted allogeneic stem cell transplantation (ASCT) for hematological malignancies. Materials and methods. Between March 2003 and December 2004, a total of 24 patients with HLA-identical sibling donors entered this study and received three doses of 3.33 Gy F-TBI separated by 24 h and cyclophosphamide or etoposide. Results. At a median follow-up of 37 months (range 29-47 months), 4 of the 24 patients (16.6%) died of TRM. Relapse occurred in 10 patients at a median of 9 months (range 2-18 months). Overall, 13 of 24 patients (54%) died. Relapse was the most common cause of death (9/13). The 2-year actuarial survival rate was 46% (±11%). Conclusion. In our experience, ASCT conditioned with F-TBI was associated with low TRM but a high early relapse rate in patients with hematological malignancies. © 2007 Japan Radiological Society.