Decreased RBCTs after reduced intensity conditioning allogeneic stem cell transplantation: predictive value of prior...

RBCT (RBCT) requirements of stem cell transplant (SCT) recipients are often substantial and may be related to transplant type.

An analysis was done of RBCT requirements and Hb recovery kinetic in the first 60 days after HLA-identical sibling allogeneic SCT in a series of 110 consecutive patients treated for various malignant diagnoses. Patients were prepared with either an antithymocyte globulin (ATG) and reduced intensity chemotherapy-based conditioning (RIC) (n=64) or a myeloablative conditioning regimens (MAC; n=46). Patients received marrow (n=64) or PBPCs (n=46).

Overall, intensity of conditioning regimen (RIC vs. MAC; p=0.0005) and graft source (PBPC vs. marrow; p<0.0001) independently predicted RBCT requirements. Hb recovery was accelerated after RIC when compared to MAC allo-SCT (p=0.02). In RIC patients, RBCTs were inversely correlated to Hb level before conditioning (p<0.0001) and the dose of ATG (p=0.009). Moreover, Hb level before allo-SCT significantly influenced Hb recovery kinetic after RIC but had no impact on RBCT requirements and Hb recovery after MAC.

Thus, RIC conditioning creates a different pattern of erythropoiesis recovery as compared to a MAC regimen and suggest a need for studies aimed at further reducing RBCT and accelerating Hb recovery.