Irradiation-Based Myeloablative Cord Blood Transplantation for Hematologic Malignancies In Adults.

Abstract 4583

We retrospectively analyzed of the engraftment, Transplant-related complications and survival after unrelated cord blood transplantation (UCBT) using irradiation-based myeloablative conditioning in adult with hematologic malignancies. Between September 2006 and June 2010, 29 consecutive adult patients with hematological malignancies were treated with UCBT, Thirteen of them were advanced-stage disease and 11 of them were high risk or refractory disease. All patients received four fractionated 12 Gy TBI, total dose 12 g/m² cytarabine and total dose 120 mg/kg cyclophosphamide as myeloablative conditioning. The median age was 21 years; the median weight was 57 kg. Double or multiple UCB grafts were used for 17 patients, while single UCB graft for 12 patients. the median number of nucleated cells was 3.83×10⁷/kg and 5.25×10⁷/kg. All patients were given a combination of cyclosporine A (CsA) and mycophenolate mofetil (MMF) for graft-versus-host disease (GVHD) prophylaxis. All patients obtained engraftment. Median time to neutrophil≥0.5×10⁹/L was 20 days (range 14–37) and platelet engraftment in 25 patients (≥20×10⁹/L) was 35 days (range 25–49). Chimerism was assessed by PCR analysis of short tandem repeat (STR) sequences on whole blood or bone marrow weekly in cases who were fully donor chimeric from 7 days to 21 days after transplantation. 16 cases developed acute GVHD, more than grade II in three cases. Six of twenty-four patients who survived more than 100 days developed limited chronic GVHD.17 cases were alive and in hematologic remission at a median follow-up of 504 days (range 49 ~ 1245). The probability of over survival at 3 years was 58.6%. Five cases relapsed. Nine of twelve cases died of transplant related complications and infection. These results suggest that UCBT after TBI-based myeloablative conditioning could be safely and effectively used for adult patients with hematologic malignancies.