The 47th Annual Meeting of the European Society for Blood and Marrow Transplantation: Physicians - Oral Sessions (O010 – O169)

on OS and CIR remained significant in a multivariate analysis that accounted for other adverse prognostic variables.Neither differences in conditioning intensity, nor GVHD prophylaxis impacted on outcomes in patients with mutated TP53 AML.However, in this cohort further prognostic discrimination was provided by the presence of either 17p abnormalities (abn17p) or complex karyotype (CK).In patients with mutated TP53 AML without abn17p or CK the 2-year OS was 65.2% [95%CI:48.4-77.6], in comparison, patients with mutated TP53 AML with either abn17p or CK, the OS was significantly lower, 24.6% [95%CI:16.2-34],p = 0.001) (figure).The adverse effect of abn17p and CK on the OS of patients with mutated TP53 AML was retained in a multivariate analysis.In patients with mutated TP53 AML, without abn17p or CK, the CIR was 27.5% [95%CI:13.4-43.7],compared with a CIR of 65.4% ([95%CI:53.9-74.8],p = 0.001) in patients with mutant TP53 AML with either abn17p or CK.Conclusions: Our data are practice informing and assist in both risk stratification of patients allografted for mutated TP53 AML and in identification of patients likely to benefit from transplant.The adverse prognostic effect of this mutation is only evident in patients with co-occurring abn17p or CK.Even in patients with mutated TP53 AML and a cooccurring abn17p or CK, a significant proportion of patients achieved long-term survival.The frequent co-occurrence of abn17p with TP53 mutations, alongside their additive poor prognostic implication, underlines the biological importance of biallelic loss of TP53 activity in AML.