GSTM1 and myelodysplastic syndrome: Kaplan–Meier curve analyses revealed that MDS patients with a Ki-67 proliferation index of nucleated erythroid cells in the BM equal or lower than 28% or Hb levels in the peripheral blood equal or lower than 9.3 g/dL showed a significantly higher risk of developing transfusion-dependence within 1 year (Suppl.