Interactive diagnostics in the indication to allogeneic SCT in AML

Abstract

Owing to the heterogeneity of AML, the indication for allogeneic SCT (allo-SCT) requires an exact definition of the individual subentity and risk category. A comprehensive diagnostic approach is needed, which combines cytomorphology, cytogenetics, FISH, molecular genetics and immunophenotyping. Whereas the categorization in three prognostic karyotype groups is well established, rare recurrent aberrations as the unfavorable t(8;16)(p11;p13), inv(3)(q21q26) and t(6;9)(p23;q34) must also be considered. In normal karyotype, PCR analyses reveal prognostically relevant mutations in >85% of cases, and a molecular data set composed of the FLT3-ITD, MLL-PTD, NPM1 and CEBPA mutations was found able to guide the selection of patients for allo-SCT. Some novel markers as the WT1 mutations might further contribute to risk stratification in normal karyotype. The panel of minimal residual disease parameters is being expanded at this time, for example, by quantitative PCR for the NPM1 mutations. Immunophenotyping allows the definition of leukemia-associated phenotypes in nearly all cases, but its position in the indication to allo-SCT has to be validated. Thus, the optimization of the indication to allo-SCT is an ongoing process that should remain in continuous interaction with the increasing panel of known genetic markers and diagnostic methods.