Acute megakaryoblastic leukemia

A type of acute myeloid leukemia

Classification
External resources

Acute megakaryoblastic leukemia (AMKL) is a rare form of acute myeloid leukemia (AML) characterized by the proliferation of megakaryoblasts, which are immature precursors of megakaryocytes, the cells responsible for the production of platelets.

Pathophysiology

AMKL is defined by the presence of more than 20% blasts in the bone marrow or peripheral blood, with at least 50% of these blasts being of megakaryocytic lineage. The disease is associated with various genetic abnormalities, including chromosomal translocations and mutations in genes such as GATA1, JAK2, and MPL.

Clinical Presentation

Patients with AMKL may present with symptoms related to bone marrow failure, such as anemia, thrombocytopenia, and neutropenia. Common symptoms include fatigue, easy bruising or bleeding, and increased susceptibility to infections. In some cases, patients may also present with hepatosplenomegaly or lymphadenopathy.

Diagnosis

The diagnosis of AMKL is based on morphological, immunophenotypic, and cytogenetic analysis of bone marrow or peripheral blood samples. Flow cytometry is used to identify the expression of specific markers such as CD41, CD42, and CD61 on the surface of megakaryoblasts. Cytogenetic analysis can reveal characteristic chromosomal abnormalities associated with the disease.

Treatment

The treatment of AMKL typically involves chemotherapy regimens similar to those used for other subtypes of AML. In some cases, hematopoietic stem cell transplantation may be considered, especially for patients with high-risk features or those who do not respond to initial therapy. The prognosis of AMKL varies depending on factors such as age, genetic abnormalities, and response to treatment.

Prognosis

The prognosis of AMKL is generally poor, with overall survival rates lower than those for other types of AML. However, certain subgroups, such as children with Down syndrome who develop AMKL, may have a better prognosis due to a higher sensitivity to chemotherapy.

Related pages

• Acute myeloid leukemia
• Megakaryocyte
• Platelet
• Bone marrow

Gallery

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  Micrograph of acute megakaryoblastic leukemia

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  Acute megakaryoblastic leukemia