Higher Incidence of Relapse with Peripheral Blood Rather Than Marrow as a Source of Stem Cells in Adults with Acute Myelocytic Leukemia, but Not in Adults with Acute Lymphocytic Leukemia Autografted during the First Remission

The cell source for autologous stem cell transplantation has shifted since 1994 from bone marrow (BM) to peripheral blood (PB). However, no study has compared outcomes. We analyzed 2165 adults with acute myelocytic leukemia (AML) and 1545 adults with acute lymphocytic leukemia (ALL) in first complete remission (CR1) who received autografts (AML: 1607 PB and 558 BM, ALL: 1126 PB and 416 BM) from 1994 to 2006.

AML: Relative to the time of CR1, PB transplants were performed earlier than BM transplants. Since a poorer outcome was associated with a shorter interval from CR1 to PB transplantation, patients were divided into three groups: BM, early PB (≤ 80 days after CR1) and late PB transplants. BM recipients were younger, and more received total body irradiation. In multivariate analysis, transplant-related mortality was not different among groups, but relapse incidence (RI) was higher for early PB (p = .0006) and late PB (p = .01) compared to BM (56 ± 3%,.46 ± 2%, 39 ± 2% respectively). Earlier PB (p= .02) and later PB transplants (p= .06) were associated with a lower three year LFS rate than marrow (36± 3%, 46 ± 2%, 52± 2% respectively).

ALL:: In multi variate analysis the only poor prognostic factors were a high white cell count at diagnosis and cytogenetics (presence of the Phi/bcr-abl). The RI and LFS at 2 years were identical in patients receiving BM and PB ( 45 ± 3% vs 47 ± 2% and 47 ± 3% vs 46 ± 2% respectively)

In conclusion, in AML patients autografted in CR1 but not in ALL, risk of relapse was lower with BM than with PB, independent of the CR1 to transplantation interval.