Clinical Significance of Myeloblasts Percentage in the De Novo Acute Myeloid Leukemia with Erythroid Hyperplasia

Objects: Investigate the clinical significance of myeloblasts percentage in the de novo acute myeloid leukemia(AML) with erythroid hyperplasia from a single center of China

Methods: We retrospectively collected information regarding clinical characteristics and survival data from de novo101 patients with newly diagnosed AML with erythroid hyperplasia (> 50% erythroid cells) from 2002-2016. The total patients were divided into two groups according to the myeloblasts percentage in total marrow cells. Cases with<20% total myeloblast was defined as low-blast group while cases with>20% total myeloblast was defined as high-blast group. Median follow-up of patients was 10.03 months.

Results:1.A total of 101 patients were diagnosed as de novo acute myeloid leukemia with erythorid hyperplasia according to WHO2008 criteria, 70 patients was classified as low-blast group, 31 patients was classified as high-blast group. Compared with high-blast group, in the low-blast group, the median age was older (39.8 vs 33.3, p=0.044), male was predominant (71.4% vs 48.4%, p=0.01). But complete remission (CR) after induction chemotherapy was lower in high-blast group(44.4% vs 57.4%, p=0.019).There were no difference in the white blood count(WBC), chromosome karyotype and incidence of various gene mutations.

2. The median survival time in the low-blast group and high-blast group was 39.19 months and 23.43 months respectively. 3-year overall survival(OS) was 53.1% and 43.4%(p=0.668), 3-year disease free survival(DFS) was 71.4% and 47.8% (p=0.297).

3. Univariable analysis showed that OS of 101 AML patients was correlated with prognosis subtype, remission of induction chemotherapy, transplant and relapse, and not related with myeloblast percentage exceed 20% of total morrow cells or not, WBC, age, gender and induction regimens. DFS of the all patients was correlated with the remission of induction chemotherapy and prognosis subtype. Multivariable analysis showed that OS was only correlated with remission of induction chemotherapy and transplant, DFS was only correlated with remission of induction chemotherapy.

Conclusions: In the AML patients with erythroid hyperplasia with<20% total myeloblast, the age was older and CR was higher than that with >20% total myeloblast, but the survival was similar in both patients regardless of myeloblast percentage. The patients who attained CR after induction chemotherapy and received transplantation would get better outcome.