An analysis of 97 previously diagnosed de novo adult acute erythroid leukemia patients following the 2016 revision to World Health Organization classification.

Background: The incidence of acute erythroid leukemia subtype (AEL) is rare, accounting for 5% of cases of acute myeloid leukemia (AML), and the outcome is dismal. However, in 2016 revision to the WHO classification, the subcategory of AEL has been removed. Myeloblasts are redefined as the percentage of total marrow cells, not non-erythroid cells. Therefore, the previously diagnosed AEL cases are currently diagnosed as AML or myelodyspalstic syndrome (MDS) according to new criteria.

Methods: We respectively reviewed cases of 97 de novo previously diagnosed AEL and all the patients were diagnosed as AML or MDS according to the new classification scheme, and then the clinical characteristics of these two subtypes were compared. Statistical analyses were performed by SPSS software version 18.0.

Results: The median age was 37 years-old, the two-thirds of previous AEL cases were diagnosed as MDS, and there was no obvious difference between two subtypes except for male/female ratio and age. Cytogenetic, rather than MDS/AML subtypes, can better represent the prognostic factor of previously diagnosed AEL patients. When the cytogenetic risk of patients belonged to MRC intermediate category and age were below 40 years-old in previous AEL cases, the patients who received induction chemotherapy without transplantation had a similar survival compared with the patients who underwent transplantation (3-year OS: 67.2% vs 68.5%).

Conclusions: Cytogenetic, rather than MDS/AML subtypes, can better represent the prognostic factor of previously diagnosed AEL patients. Transplantation was a better choice for those whose cytogenetic category was unfavorable.