Reversal of marrow fibrosis in agnogenic myeloid metaplasia by allogeneic peripheral blood stem cell transplantation.

Agnogenic myeloid metaplasia (AMM) is a clonal hematopoietic stem cell disorder characterized by bone marrow fibrosis, extramedullary hemopoiesis, splenomegaly and a leukoerythroblastic blood picture. Current standard therapies using hydroxyurea, interferon, androgens or corticosteroids have not shown to prolong survival of patients with AMM. In this study, we performed a curative approach using an HLA-matched sibling as a donor for allogeneic peripheral blood stem cell transplantation (PBSCT) for a 45-year-old woman with AMM. Busulfan and cyclophosphamide were given as a conditioning regimen from day -7 to day -2 with cyclosporinA and methotrexate as post-transplant immunosuppressive therapy. Donor PBSCs were mobilized by G-CSF at 16 microg/kg/day for five days and transplantation was performed on March 2-3, 2000. The patient rapidly engrafted within 2 weeks after PBSC infusion without evidence of graft versus host disease. Her blood counts and bone marrow 2 years after transplantation were normal with full donor pattern by molecular analysis. In conclusion, marrow fibrosis can be reverted to normal by allogeneic PBSCT. Allogeneic PBSCT should thus be offered to AMM patients if an HLA-matched sibling is available. This report represents the first SCT for AMM in Thailand.