This study evaluates the efficacy of high-dose post-transplantation cyclophosphomide as graft-versus-host disease (GVHD) prophylaxis after allogeneic stem cell transplantation in patients with different risk of GVHD. The risk-adapted strategy involves using single-agent cyclophosphomide in recipients of matched bone marrow graft, and combining cyclophosphomide with tacrolimus and mycophenolate mofetil in recipients of matched peripheral blood stem cells and mismatched bone marrow.

Inclusion Criteria:

• Patients must have an indication for allogeneic hematopoietic stem cell transplantation
• Signed informed consent
• Patients with a donor available. The donor and recipient must be identical at at least one allele of each of the following genetic loci: HLA-A, HLA-B, HLA-Cw, HLA-DRB1, and HLA-DQB1. A minimum match of 5/10 is required for related donor. A minimum match of 8/10 is required for unrelated donor.
• No second tumors
• No severe concurrent illness

Exclusion Criteria:

• Moderate or severe cardiac dysfunction, left ventricular ejection fraction <50%
• Moderate or severe decrease in pulmonary function, FEV1 <70% or DLCO<70% of predicted
• Respiratory distress >grade I
• Severe organ dysfunction: AST or ALT >5 upper normal limits, bilirubin >1.5 upper normal limits, creatinine >2 upper normal limits
• Creatinine clearance < 60 mL/min
• Uncontrolled bacterial or fungal infection at the time of enrollment
• Requirement for vasopressor support at the time of enrollment
• Karnofsky index <30%
• Pregnancy
• Somatic or psychiatric disorder making the patient unable to sign informed consent