A Two-Step Approach to Bone Marrow Transplant Using Cells From Two Partially-Matched Relatives

This phase II clinical trial studies how well two donors stem cell transplant work in treating patients with high-risk hematologic malignancies. After receiving radiation to help further treat the disease, patients receive a dose of donors' T cells. T cells can fight infection and react against cancer cells. Two days after donors' T cells are given, patients receive cyclophosphamide (CY) to help destroy the most active T cells that may cause tissue damage (called graft versus host disease or GVHD). Some of the less reactive T cells are not destroyed by CY and they remain in the patient to help fight infection. A few days after the CY is given, patients receive donors' stem cells to help their blood counts recover. Using two donors' stem cell transplant instead of one donor may be more effective in treating patients with high-risk disease and may prevent the disease from coming back.