OUTLINE: This is a randomized study. Patients are randomized to one of two treatment arms. Arm I: Patients receive fluconazole orally or IV daily beginning at start of conditioning regimen and continuing until day 180 or until 4 weeks after stopping corticosteroids (if it occurs between days 120-180). Arm II: Patients receive oral fluconazole daily beginning at start of conditioning regimen and continuing until day 0. Patients then receive itraconazole orally or IV daily beginning on day 0 and continuing until day 180, or until 4 weeks after stopping corticosteroids (if it occurs between days 120-180).