2. Cord blood transplantation to adult patients:

Article Outline

• Copyright

Since 1993, the National Cord Blood Program has provided cord blood transplants to 1750 recipients worldwide, of whom 396 ≥16 years old (22.6%). Of the adults, 65% were ≥25 years old, 90% had hematologic malignancies, 33% had advanced disease (IBMTR classification), 13% had received a prior auto or allograft and 11% received double-unit transplants. Of single-unit transplant recipients, 22% had 1, 66% had 2 and 10% had 3 HLA mismatches (HLA-A and -B at serological resolution level, DRB1 at the allele level). TNC doses were below 5 × 10⁷ in all but 5 patients. Engraftment was associated with TNC dose (P = 0.004) and HLA-matching (p = 0.003), especially when recipients of mismatched only in the GvH direction were counted as matched (p = 0.001). Significant differences in the probability of engraftment were also related to the conditioning regimens and to the use of double unit transplantation. Acute GvHD grade III–IV developed in 25% of cases, and was lower (≈10%) in cases without HLA mismatches in the GvHD direction. This was not significant in this sample, however. The probability of relapse was ≈15% and was lower in cases with lower IBMTR risk factors (NS in this sample). Within the adult group (age = 16-67), age at transplantation was not significantly related to the probability of survival at 1 or 5 years. The difference in 1 year survival between recipients of grafts with < and grafts with ≥2.5 × 10⁷ was not significant (28% vs. 34%). The absence of HLA rejection mismatches was significantly associated: with survival at 1 year (survival = 68% vs. 27%, P = 0.005). Overall survival was 23% at 5 years. Engraftment and survival were significantly better in a group of 45 patients given a two-unit transplant, the majority of which also were treated with fludarabine-containing regimens. These results extend the data on adult recipients of cord blood grafts beyond those previously reported.