Promising Progression-Free Survival for Patients Low and Intermediate Grade Lymphoid Malignancies after Nonmyeloablative Umbilical Cord Blood Transplantation

Nonmyeloablative hematopoietic cell transplantation (HCT) has been used to treat patients with advanced or high-risk lymphoid malignancies. We studied 65 patients (median age 46 years) receiving an umbilical cord blood (UCB) graft after a single conditioning regimen consisting of cyclophosphamide (50 mg/kg) on day −6, fludarabine (40 mg/m2) daily on days −6 to −2, as well as a single fraction of total-body irradiation (TBI) (200 cGy) along with cyclosporine mycophenolate mofetil immunosuppression. Median time to neutrophil and platelet recovery was 7.5 days (range: 0-32) and 46 days (range: 8-111), respectively. Cumulative incidences of grade II-IV, grade III-IV acute, and chronic graft-versus-host disease (aGVHD, cGVHD) were 57% (95% confidence interval [CI]: 43%-70%), 25% (95% CI: 14%-35%), and 19% (95% CI: 9%-29%), respectively. Transplant-related mortality at 3 years was 15% (95% CI: 5%-26%). Median follow-up was 23 months. The progression free-survival (PFS), current PFS and overall survival (OS) were 34% (95% CI: 21%-47%), 49% (95% CI: 36%-62%), and 55% (95% CI: 42%-70%) at 3 years. Based on our data, we conclude that a nonmyeloablative conditioning regimen followed by UCB transplantation is an effective treatment for patients with advanced lymphoid malignancies who lack a suitable sibling donor.