Eligible patients are those with profound granulocytopenia (≤ 500 neutrophil granulocytes) and persistent or recurrent fever despite broad-spectrum antibacterial therapy of a minimum of 36-48 hours duration. Patients are stratified according to the type of the transplantation (human leukocyte antigen [HLA] matched/related versus HLA-mismatched/unrelated) and randomized into one of the following treatment arms: Caspofungin alone (50 mg/day with a loading dose of 70 mg on day 1), liposomal amphotericin B alone (3 mg/kg/day), or the combination of caspofungin and liposomal amphotericin B (similar dosages as in the single-drug treatment arms).