Is acute myelomonocytic leukemia (M4) severe?

Generally, acute myeloid leukemia (AML) subtype M4 is considered a severe disease, with prognosis varying significantly depending on individual circumstances. If any symptoms occur, prompt medical attention is recommended. A detailed analysis is as follows:

Acute myeloid leukemia M4 is one of the more severe subtypes within AML, characterized by abnormal proliferation of both granulocytes and monocytes. It is prone to cause serious complications. However, prognosis varies considerably based on patient age, cytogenetic features, and treatment strategies.

In terms of disease severity, M4 leukemia cells proliferate rapidly, not only suppressing normal bone marrow hematopoiesis but also frequently infiltrating extramedullary tissues—such as causing hepatosplenomegaly, skin infiltration, and central nervous system involvement. Additionally, patients face a very high risk of early infections. Without timely intervention, the natural course of the disease is short and mortality is high.

Regarding prognostic stratification, younger patients (<60 years) without high-risk chromosomal abnormalities and those carrying favorable gene mutations may achieve a 5-year event-free survival rate of 40%–50% after standard treatment. In contrast, older patients (>60 years), especially those with comorbidities or high-risk genetic mutations, often have poor treatment tolerance, lower remission rates, and a 5-year survival rate typically below 20%, indicating a more aggressive disease course.

In summary, AML-M4 should be recognized as a serious condition, yet it is not incurable. After diagnosis, prompt evaluation at a hematology specialty center to determine prognostic risk group and establish an individualized treatment plan is essential. For eligible younger patients, actively pursuing allogeneic hematopoietic stem cell transplantation can significantly improve the likelihood of cure, helping to prevent disease progression due to delayed treatment.