Telefonieren und Freizeit eine Analyse von Umfrage- und Zeitverwendungsdaten

UuStB Koeln(38)-920106369 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Acute myeloid leukemia with biallelic CEBPA gene mutations and normal karyotype represents a distinct genetic entity associated with a favorable clinical outcome.

Purpose CEBPA mutations are found as either biallelic (biCEBPA) or monoallelic (moCEBPA). We set out to explore whether the kind of CEBPA mutation is of prognostic relevance in cytogenetically normal (CN) acute myeloid leukemia (AML). Patients and Methods: Four hundred sixty-seven homogeneously treated patients with CN-AML were subdivided into moCEBPA, biCEBPA, and wild-type (wt) CEBPA patients. The subgroups were analyzed for clinical parameters and for additional mutations in the NPM1, FLT3, and MLL genes. Furthermore, we obtained gene expression profiles using oligonucleotide microarrays. Results: Only patients with biCEBPA had an improved median overall survival when compared with patients with wtCEBPA (not reached v 20.4 months, respectively; P = .018), whereas patients with moCEBPA (20.9 months) and wtCEBPA had a similar outcome (P = .506). Multivariable analysis confirmed biCEBPA, but not moCEBPA, mutations as an independent favorable prognostic factor. Interestingly, biCEBPA mutations, compared with wtCEBPA, were never associated with mutated NPM1 (0% v 43%, respectively; P < .001) and rarely associated with FLT3 internal tandem duplication (ITD; 5% v 23%, respectively; P = .059), whereas patients with moCEBPA had a similar frequency of mutated NPM1 and a significantly higher association with FLT3-ITD compared with patients with wtCEBPA (44% v 23%, respectively; P = .037). Furthermore, patients with biCEBPA showed a homogeneous gene expression profile that was characterized by downregulation of HOX genes, whereas patients with moCEBPA showed greater heterogeneity in their gene expression profiles. Conclusion: Biallelic disruption of the N and C terminus of CEBPA is required for the favorable clinical outcome of CEBPA-mutated patients and represents a distinct molecular subtype of CN-AML with a different frequency of associated gene mutations. These findings are of great significance for risk-adapted therapeutic strategies in AML

Monoallelic <em>CEBPA</em> mutations in normal karyotype acute myeloid leukemia: Independent favorable prognostic factor within <em>NPM1</em> mutated patients.

We and others have shown that cytogenetically normal (CN)-AML patients with biallelic CEBPA gene mutations (biCEBPA) represent a molecularly distinct group with a favorable prognosis. Patients carrying a monoallelic CEBPA mutation (moCEBPA), however, show no different outcome compared to patients with wildtype CEBPA, and these mutations are frequently associated with mutated NPM1 or FLT3-ITD. So far, no molecular or clinical hallmark has been identified to prognostically distinguish moCEBPA patients from patients with wildtype CEBPA. Therefore, we used the data of 663 CN-AML patients treated within the AMLCG 1999 trial to explore the prognostic value of moCEBPA in the context of concomitant clinical and molecular markers (mutated NPM1, FLT3-ITD). Multiple Cox regression in 515 patients adjusting for all available potential confounders revealed that the NPM1 mutation modified the prognostic value of moCEBPA with respect to overall survival (OS, p = 0.017) and event-free survival (EFS, p = 0.011). MoCEBPA was beneficial in NPM1 mutated patients: adjusted OS-hazard ratio (HR) 0.09, 95% confidence interval (CI) 0.01-0.63, p = 0.016; EFS-HR (95% CI) 0.16 (0.04-0.65), p = 0.010. In contrast, moCEBPA had no prognostic impact in patients with wildtype NPM1: OS-HR (95% CI) 1.08 (0.59-1.97), p = 0.804; EFS-HR (95% CI) 1.12 (0.64-1.96), p = 0.682. We found no prognostic effect modification for moCEBPA by FLT3-ITD. The presence of a moCEBPA mutation was shown to be associated with prolonged survival in NPM1 mutated CN-AML patients. Confirmation of these results in larger studies will clarify whether an additional moCEBPA mutation influences the risk stratification of patients with an NPM1 mutated/FLT3-ITD positive genotype

The <em>FLT3</em>ITD mRNA level has a high prognostic impact in <em>NPM1</em> mutated, but not in <em>NPM1</em> unmutated, AML with a normal karyotype.

The impact of a FLT3-internal tandem duplication (FLT3ITD) on prognosis of patients with acute myeloid leukemia (AML) is dependent on the ratio of mutated to wild-type allele. In 648 normal karyotype (NK) AML patients, we found a significant independent effect of the quantitative FLT3ITD mRNA level-measured as (FLT3ITD/wtFLT3)/(FLT3ITD/wtFLT3 + 1)-on outcome. Moreover, this effect was clearly seen in 329 patients with a mutated NPM1 gene (NPM1(+)), but not in 319 patients without a NPM1 mutation (wtNPM1). In a multivariate Cox regression model, the quantitative FLT3ITD mRNA level showed an independent prognostic impact on overall survival (OS) and relapse-free survival (RFS) only in the NPM1(+) subgroup (OS: hazard ratio, 5.9; [95% confidence interval [CI]: 3.1-11.2]; RFS: hazard ratio, 7.5 [95% CI: 3.4-16.5]). The FLT3ITD mRNA level contributes to relapse risk stratification and might help to guide postremission therapy in NPM1-mutated AML

NPM1 but not FLT3-ITD mutations predict early blast cell clearance and CR rate in patients with normal karyotype AML (NK-AML) or high-risk myelodysplastic syndrome (MDS).

Mutations in the NPM1 gene represent the most frequent genetic alterations in patients with acute myeloid leukemia (AML) and are associated with a favorable outcome. In 690 normal karyotype (NK) AML patients the complete remission rates (CRs) and the percentage of patients with adequate in vivo blast cell reduction 1 week after the end of the first induction cycle were significantly higher in NPM1(+) (75% and 80%, respectively) than in NPM1(-) (57% and 57%, respectively) patients, but were unaffected by the FLT3-ITD status. Multivariate analyses revealed the presence of a NPM1 mutation as an independent positive prognostic factor for the achievement of an adequate day-16 blast clearance and a CR. In conclusion, NPM1(+) blast cells show a high in vivo sensitivity toward induction chemotherapy irrespective of the FLT3-ITD mutation status. These findings provide insight into the pathophysiology and help to understand the favorable clinical outcome of patients with NPM1(+) AML