Analyses of minimal residual disease based on Flt3 mutations in allogeneic peripheral blood stem cell transplantation

Purpose Activating Flt3 mutations are observed in about 30% of patients with acute myeloid leukaemia (AML) and individual Flt3 mutations are applicable for minimal residual disease (MRD) analyses.Methods We investigated the MRD status in four AML patients carrying different Flt3 mutations (three patients with Flt3 length mutations of the juxtamembrane domain, one patient carrying a mutation of the Flt3 tyrosine kinase domain, i.e. Flt3-TKD mutation) who underwent allogeneic peripheral blood stem cell transplantation (PBSCT). Residual leukaemia cells were retrospectively determined by real-time PCR at different time points.Results We can demonstrate a good correlation between the course of MRD status and clinical events in all four investigated patients.Conclusion These examples demonstrate the potential impact of Flt3 based MRD status not only after but also prior to allogeneic PBSCT.