Acute Monocytic Leukemia

Definition

Definition of Acute Monocytic Leukemia
Acute monocytic leukemia (AMoL, or AML-M5) is considered a type of acute myeloid leukemia.

Symptoms

Symptoms of Acute Monocytic Leukemia
The symptoms for leukemia often start out like many common illnesses with fatigue and fevers. What may prompt a trip to the doctor are infections that do not get better with antibiotics, abnormal bruising or bleeding, swollen lymph glands,excessive fatigue, and bone or joint pain.

Causes

Causes of Acute Monocytic Leukemia
M5 is associated with characteristic chromosomal abnormalities, often involving Chromosome 11 at 11q23 or t(9;11) affecting the MLL locus, however the MLL translocation is also found in other AML subtypes. MLL is believed to be prognostically unfavorable in AML-M5 compared to other genetic alterations involving MLL such as t(9;11). The t(8;16) translocation in MLL is associated with hemophagocytosis.

Diagnosis

Diagnosis of Acute Monocytic Leukemia
In order to fulfill World Health Organization (WHO) criteria for AML-5, a patient must have greater than 20% blasts in the bone marrow, and of these, greater than 80% must be of the monocytic lineage. A further subclassification (M5a versus M5b) is made depending on whether the monocytic cells are predominantly monoblasts (>80%) (acute monoblastic leukemia) or a mixture of monoblasts and promonocytes (<80% blasts). Monoblasts can be distinguished by having a roughly circular nucleus, delicate lacy chromatin, and abundant, often basophilic cytoplasm. These cells may also have pseudopods. By contrast, promonocytes have a more convoluted nucleus, and their cytoplasm may contain metachromatic granules. Monoblasts are typically MPO-negative and promonocytes are MPO variable. Both monoblasts and promonocytes stain positive for non-specific esterase (NSE), however NSE may often be negative.

Treatment

Treatment of Acute Monocytic Leukemia
The initial treatment (induction) uses a combination of chemotherapy drugs to achieve a remission (ridding the bone marrow of the visible leukemic cells). Following this is the consolidation treatment which involves very intense chemotherapy to try to eliminate any cells that might be "hiding" in the body. Part of the treatment for AML also involves antibiotics, nutritional support, and transfusions when necessary because the doses of chemotherapy are so toxic that patients require extra supportive care.

Prognosis

Prognosis of Acute Monocytic Leukemia
Consult with your doctor.

Prevention

Prevention of Acute Monocytic Leukemia
Consult with your doctor.