CD38 and myelodysplastic syndrome: Abnormal expression of differentiation/proliferation-associated immunophenotypes (CD19, CD38 and CD117), synchronous expression of non-stage specific immunophenotypes (CD15, CD11b) and expression of non-lineage specific immunophenotypes (CD4, CD56, CD7) in CD34+ blasts may reflect the developmental disorder of MDS clonal cells.