Kategorie: Maligní lymfomy a leukémie
Téma: Acute myeloid leukemia - Clinical
Číslo abstraktu: P052
Autoři: MD Stefani Parmentier; Michael Kramer; Katharina Koch; Brigitte Mohr, PhD; M.D. Christian Thiede; MD Christoph Röllig; MD Mathias Hänel; MD Norbert Schmitz; Dr. Kerstin Schäfer-Eckart; Walter E. Aulitzky; MD Wolfgang E. Berdel; Prof. MD Hubert Serve; Stefan W. Krause; prof. MUDr. Jiří Mayer, CSc.; M. Bomhäuser; MD Gerhard Ehninger; MD Marcus Schaich
Acute erythroleukemia (AEL) represents a rare type of acute myeloid leukemia accounting for less than 5% of all cases. So far, according to WHO classification this AML entity is thought to have a poor prognosis in itself.
We assessed the influence of relevant clinical and demographic parameters, FLT3-ITD, NPM1 status and cytogenetics on complete remission rates (CR), overall survival (OS) and event free survival (EFS) separately in AEL and non-AEL patients.
3267 patients with newly diagnosed AML were treated according to the protocols of the AML96, AML2003 or AML60+ studies of the Study Alliance Leukemia (SAL). Informed consent was obtained by all patients. 116 of these patients had acute erythroleukemia (AEL). In only 78 of these cases slides for systematic morphologic review were available. Only cases with morphological review were included into subgroup analysis.
After morphological review, three diagnostic groups could be separated according to WHO 2008: acute erythroid/myeloid leukemia (n=54; AML M6a according to FAB), pure erythroid leukemia (n=4; AML M6b according to FAB) and acute myeloid leukemia with multilineage dysplasia (n=20). No significant differences between these distinct groups could be elucidated, but all BM harborded severe dysplastic features and mostly multilineage dysplasia. Compared to non-AEL AML, NPM1 and FLT3-ITD mutations were found in 13.3% and 6.3% of the patients with AEL and in 32.1% and 20.7% of the patients with non-AEL AML (p=0.002, p=0.008), respectively. All patients with AEL and NPM1 mutations were de novo AMLs and had normal cytogenetics. Several cytogenetic aberrations, most of them associated with poor prognosis, are found more often in the AEL cohort than in the non-AEL AML cohort (Trisomie 8: 16.3% vs. 9%, p=0.026; del(5q): 12.5% vs. 6.6%, p=0.038; -7: 12.5% vs. 5%, p=0.003; complex aberrant: 27.5% vs. 13.3%, p<0.001; abnl 17p: 11.3% vs. 4.2%, p=0.003; other monosomies: 16.3% vs. 5%, p<0.001). Despite these differences, no significant differences in CR rates, OS and EFS were found between both groups. This finding was confirmed in a multivariate analysis including cytogenetics, molecular markers and clinical parameters (LDH, WBC, blast count, platelet count and ECOG). According to the analysis, AEL morphology was not an independent prognostic factor for OS and EFS. Within the AEL group, patients with monosomy 7 (n=10), complex aberrant karyotype (n=22) and abnl 17p had a shorter median OS (5.7, 5.2, 4.3 months) compared to patients with AEL and not such aberrancies (20.4, 22.3, 18.9 months) (p=0.001, <0.001, 0.015), respectively. A complex aberrant karyotype was found more often in patients with secondary AEL than in patients with de novo AEL (p=0.024).
Summary / Conclusion:
According to our data, the characteristic morphological features of acute erythroleukemia do not confer an unfavorable prognosis in itself. Compared to non-AEL AML, cytogenetic aberrations associated with poor prognosis are found more often in patients with AEL, but it confers only within the AEL group to a significant worse OS. NPM1 and FLT3-ITD mutations were much less common in patients with AEL.
Datum přednesení příspěvku: 14. 6. 2013