OBJECTIVES: I. Determine the maximum tolerated dose of T-cells photochemically treated with psoralen and ultraviolet A given with peripheral stem cell transplantation in patients with hematologic malignancies or bone marrow failure myelodysplastic syndrome. II. Assess the toxicity of this treatment in these patients. III. Evaluate this regimen in terms of prevention of graft versus host disease and control of malignancy in these patients.