OBJECTIVES: I. Compare the efficacy of itraconazole versus fluconazole in reducing the incidence of breakthrough Aspergillus infections in patients undergoing allogeneic peripheral blood stem cell or bone marrow transplantation. II. Compare the incidence of combined mold/yeast infections and the use of alternative systemic antifungal treatments in these patients on this regimen. III. Compare the toxic effects of these two drugs in these patients. IV. Determine the survival rate of these patients.