De Novo and Secondary Acute Myeloid Leukemia, Real World Data on Outcomes from the French Nord-Pas-De-Calais Picardie Acute Myeloid Leukemia Observatory

Background.Population-based registries may provide data complementary to that from clinical intervention studies. Registries with high coverage of the target population reduce the impact of selection on outcome and the subsequent problem with extrapolating data to nonstudied populations like secondary Acute Myeloid Leukemia (AML). Actually, secondary AML are frequently excluded from clinical trials so the registries constitute the only way to fine data for establishing recommendations for the management of these patients in the real world.

Method. The French Nord-pas-de-calais Picardie AML observatory containing 1 582 AML patients diagnosed between 2000 and 2015. We compared 974 primary AML to 514 Secondary AML include AML arising from a pre-existing myelodysplastic (n=211), myeloproliferative (n=88) or myelodysplastic/myeloproliferative (n=57) disease and therapy related AML (t-AML) (n=158).

Results.Median survival and 5 years overall survival were respectively 420 days [95%IC: 349-491] and 32% for patients with de novo AML; 157 days [95%IC: 118-196] and 7% for patients with secondary AML. 1101 patients were classified according to the MRC as favorable, intermediate and unfavorable, respectively 18(5.2%), 178(51.9%) and 147(42.9%) patients with secondary AML including 100(29.2%) complexes karyotypes and 117(15.4%), 468(61.7%) and 173(22.8%) patients with de novo AML including 121 (15.9%) complexes karyotypes. 987 patients were classified according to the ELN as favorable, intermediate-1, intermediate-2 and unfavorable for respectively 35(11.7%), 53(17.7%), 67(22.%) and 144(48.2%) patients with secondary AML and 219(31.8%), 167(24.%), 136(19.8%) and 166(24.1%) patients with de novo AML. The age at diagnosis was significantly different (p < 10^-3) with a median of 72.6 years for secondary AML and 63.2 for de novo AML. 206 (40.4%) patients with secondary AML received demethylating agents versus 184 (19%) for de novo AML and 152(29%) received high dose chemotherapy (HDC) versus 619 (63.9%) patients with de novo AML. Best supportive care was the only treatment for 170 (17.5%) de novo AML and 164 (31.9%) secondary AML patients. For patients over than 60 years old, median survival and 5 years overall survival were respectively 182 days [95%IC: 136.5-127.4] and 12.9% for 559 patients with de novo AML; 128 days [95%IC: 95.0-161.0] and <4% for 413 patients with secondary AML.

Conclusion.The poor prognosis of secondary and t- AML is confirmed by this registry study. Possible explanations for this worse outcome could be older age at diagnosis and increased frequency of complex karyotypes which lead to less intensive therapy or supportive care only. In this specific population, the choice of demethylating agent therapy was frequently made because of the weak efficacy of HDC and increased frequency of side effects in this vulnerable group.