Fig. 2: Integrated approaches for understanding pathogenesis of acquired donor cell-derived genetic abnormalities after allogeneic stem cell transplantation.

Multifactorial and multiple-hit mechanisms may play roles in development of acquired cytogenetic abnormalities in donor cell-derived leukemia (DCL) and donor cell-derived clonal cytogenetic abnormalities of undetermined significance (CAUS). Although well-known cytogenetic abnormalities associated with hematological malignancies can occur in DCL and CAUS, they tend to appear at a much lower level in CAUS than in DCL. A combined approach including clinical correlation, gene mutations, immunophenotyping, and pathological findings is useful to properly interpret the clinical importance of acquired cytogenetic abnormalities.