Allogeneic Peripheral Blood Stem Cell Transplants (PBSCT) May Have a Benefit in Acute Lymphoblastic Leukemia (ALL) Outcome.

Hematopoietic stem cell transplantation is a valid alternative as post-remission therapy in ALL. Our aim was analyzed retrospectively the clinical outcomes of 97 ALL patients with HLA identical sibling donors who underwent an allo PBSCT. Median age was 24 ys (2–45), advanced disease was present in 74%, conditioning without irradiation was 56%; GVHD prophylaxis with MTX/CsA was 91%; CD34⁺ median was 4.6X10⁶/kg (1.2–24); the median follow-up for surviving patients was 22 months (1.6–93). Median day for neutrophils and platelets engraftment was 15 and 13, respectively; no TBI conditioning, no MTX/CsA, were associated significantly with faster neutrophils engraftment; no MTX/CsA with platelets. Cumulative incidence (CI) for ≥ 2 aGVHD was 45%, extensive cGVHD 50%; aGVHD in patients who received TBI conditioning was 34% (P=0.04). The estimates of OS and DFS at 92 months was 21% and 31%, respectively; OS for patients >36ys was 16% (P=0.04), for patients with aGVHD 11% (P=0.03); there was a trend towards better OS and DFS in patients with cGVHD (54%, 63%; P=0.07, P=0.06). CI for relapses was 60%; relapses for cGVHD patients were 36% (P= 0.05), and there was a trend towards higher relapses in advanced disease (66%, P=0.06). TRM was 64%; in those patients with aGVHD, 73% (P=0.008). In multivariate analyses no MTX/CsA was related with the speed of platelets engraftment (P=0.007); TBI conditioning was associated with less aGVHD and TRM (P=0.05, P=0.01); aGVHD had a negative impact on OS with higher TRM (P=0.02, P=0.02). Although not confirmed in the multivariate analyses, fewer relapses, and a trend towards better OS, and DFS were found in patients with extensive cGVHD. However, further follow up will be necessary to confirm these results.