Acute erythroid leukemia.

Area of Science:

• Hematology
• Oncology
• Pathology

Background:

• Acute erythroid leukemia (AEL) is a rare subtype of acute myeloid leukemia (AML), comprising less than 5% of cases.
• AEL is characterized by predominant erythroid proliferation, with two subtypes: erythroleukemia and pure erythroid leukemia.
• Morphological findings are key for diagnosis, but AEL can overlap with other erythroid-rich hematologic malignancies.

Purpose of the Study:

• To update the understanding of AEL, including clinical, morphological, immunophenotypic, cytogenetic, and molecular aspects.
• To review the literature and specific AEL cases, with a focus on the more common erythroleukemia subtype.
• To analyze the impact of current World Health Organization (WHO) classification criteria on AEL diagnosis and prognosis.

Main Methods:

• Review of pertinent literature on AEL.
• Analysis of clinicopathologic, cytogenetic, and molecular data from AEL cases.
• Extraction of information from institutional case files.

Main Results:

• Current WHO criteria reclassify many erythroleukemia cases as other AML subtypes (e.g., AML with myelodysplasia-related changes, therapy-related AML).
• This reclassification may alter the prognostic significance for patients with the erythroleukemia subtype.
• The WHO criteria have minimal impact on the frequency and poor prognosis of the pure erythroid leukemia subtype.

Conclusions:

• The current WHO classification impacts AEL diagnosis and potentially prognosis, particularly for the erythroleukemia subtype.
• Further molecular studies, including high-throughput methods, are essential for elucidating AEL pathogenesis.
• Developing novel diagnostic and prognostic markers for AEL requires deeper molecular insights.